]> git.piffa.net Git - doc/.git/blobdiff - servizi.html
Prima stesura di Squid, da correggere
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           </ul>
         </li>
 
-        <li><a class="reference internal" href="#squid" id="id16"
-        name="id16">2&nbsp;&nbsp;&nbsp;Squid</a></li>
+        <li>
+          <a class="reference internal" href="#squid" id="id16"
+          name="id16">2&nbsp;&nbsp;&nbsp;Squid</a>
+
+          <ul class="auto-toc">
+            <li>
+              <a class="reference internal" href=
+              "#configurazione-squid-conf" id="id17" name=
+              "id17">2.1&nbsp;&nbsp;&nbsp;Configurazione:
+              squid.conf</a>
+
+              <ul class="auto-toc">
+                <li><a class="reference internal" href=
+                "#tag-maximum-object-size" id="id18" name=
+                "id18">2.1.1&nbsp;&nbsp;&nbsp;TAG:
+                maximum_object_size</a></li>
+
+                <li><a class="reference internal" href=
+                "#tag-cache-mem" id="id19" name=
+                "id19">2.1.2&nbsp;&nbsp;&nbsp;TAG:
+                cache_mem</a></li>
+
+                <li><a class="reference internal" href=
+                "#tag-minimum-object-size" id="id20" name=
+                "id20">2.1.3&nbsp;&nbsp;&nbsp;TAG:
+                minimum_object_size</a></li>
+              </ul>
+            </li>
+
+            <li>
+              <a class="reference internal" href=
+              "#negoziazione-degli-accesi-al-servizio" id="id21"
+              name="id21">2.2&nbsp;&nbsp;&nbsp;Negoziazione degli
+              accesi al servizio</a>
+
+              <ul class="auto-toc">
+                <li><a class="reference internal" href=
+                "#acl-e-http-access" id="id22" name=
+                "id22">2.2.1&nbsp;&nbsp;&nbsp;ACL e http
+                access</a></li>
+              </ul>
+            </li>
+
+            <li>
+              <a class="reference internal" href="#testare-squid"
+              id="id23" name="id23">2.3&nbsp;&nbsp;&nbsp;Testare
+              Squid</a>
+
+              <ul class="auto-toc">
+                <li><a class="reference internal" href="#wgetrc"
+                id="id24" name=
+                "id24">2.3.1&nbsp;&nbsp;&nbsp;wgetrc</a></li>
+              </ul>
+            </li>
+          </ul>
+        </li>
 
         <li>
-          <a class="reference internal" href="#apache" id="id17"
-          name="id17">3&nbsp;&nbsp;&nbsp;Apache</a>
+          <a class="reference internal" href="#apache" id="id25"
+          name="id25">3&nbsp;&nbsp;&nbsp;Apache</a>
 
           <ul class="auto-toc">
             <li><a class="reference internal" href=
-            "#pacchetti-da-installare" id="id18" name=
-            "id18">3.1&nbsp;&nbsp;&nbsp;Pacchetti da
+            "#pacchetti-da-installare" id="id26" name=
+            "id26">3.1&nbsp;&nbsp;&nbsp;Pacchetti da
             installare::</a></li>
 
             <li><a class="reference internal" href=
-            "#configurazione-di-apache" id="id19" name=
-            "id19">3.2&nbsp;&nbsp;&nbsp;Configurazione di
+            "#configurazione-di-apache" id="id27" name=
+            "id27">3.2&nbsp;&nbsp;&nbsp;Configurazione di
             Apache</a></li>
 
             <li><a class="reference internal" href="#apache-conf"
-            id="id20" name=
-            "id20">3.3&nbsp;&nbsp;&nbsp;apache.conf</a></li>
+            id="id28" name=
+            "id28">3.3&nbsp;&nbsp;&nbsp;apache.conf</a></li>
 
             <li>
               <a class="reference internal" href=
-              "#installazione-di-php" id="id21" name=
-              "id21">3.4&nbsp;&nbsp;&nbsp;Installazione di PHP</a>
+              "#installazione-di-php" id="id29" name=
+              "id29">3.4&nbsp;&nbsp;&nbsp;Installazione di PHP</a>
 
               <ul class="auto-toc">
                 <li><a class="reference internal" href=
-                "#test-del-modulo-php" id="id22" name=
-                "id22">3.4.1&nbsp;&nbsp;&nbsp;Test del modulo
+                "#test-del-modulo-php" id="id30" name=
+                "id30">3.4.1&nbsp;&nbsp;&nbsp;Test del modulo
                 php</a></li>
 
                 <li><a class="reference internal" href=
-                "#installazione-del-supporto-per-mysql" id="id23"
-                name="id23">3.4.2&nbsp;&nbsp;&nbsp;Installazione
+                "#installazione-del-supporto-per-mysql" id="id31"
+                name="id31">3.4.2&nbsp;&nbsp;&nbsp;Installazione
                 del supporto per Mysql</a></li>
 
                 <li><a class="reference internal" href=
-                "#phpmyadmin" id="id24" name=
-                "id24">3.4.3&nbsp;&nbsp;&nbsp;phpmyadmin</a></li>
+                "#phpmyadmin" id="id32" name=
+                "id32">3.4.3&nbsp;&nbsp;&nbsp;phpmyadmin</a></li>
 
                 <li><a class="reference internal" href=
                 "#installazione-del-supporto-per-postgresql" id=
-                "id25" name=
-                "id25">3.4.4&nbsp;&nbsp;&nbsp;Installazione del
+                "id33" name=
+                "id33">3.4.4&nbsp;&nbsp;&nbsp;Installazione del
                 supporto per Postgresql</a></li>
 
                 <li><a class="reference internal" href=
-                "#phppgadmin" id="id26" name=
-                "id26">3.4.5&nbsp;&nbsp;&nbsp;phppgadmin</a></li>
+                "#phppgadmin" id="id34" name=
+                "id34">3.4.5&nbsp;&nbsp;&nbsp;phppgadmin</a></li>
               </ul>
             </li>
 
             <li>
               <a class="reference internal" href="#virtual-hosts"
-              id="id27" name="id27">3.5&nbsp;&nbsp;&nbsp;Virtual
+              id="id35" name="id35">3.5&nbsp;&nbsp;&nbsp;Virtual
               hosts</a>
 
               <ul class="auto-toc">
                 <li><a class="reference internal" href=
-                "#gestione-dns" id="id28" name=
-                "id28">3.5.1&nbsp;&nbsp;&nbsp;Gestione DNS</a></li>
+                "#gestione-dns" id="id36" name=
+                "id36">3.5.1&nbsp;&nbsp;&nbsp;Gestione DNS</a></li>
 
                 <li><a class="reference internal" href=
-                "#virtual-host" id="id29" name=
-                "id29">3.5.2&nbsp;&nbsp;&nbsp;Virtual host</a></li>
+                "#virtual-host" id="id37" name=
+                "id37">3.5.2&nbsp;&nbsp;&nbsp;Virtual host</a></li>
               </ul>
             </li>
 
             <li>
               <a class="reference internal" href=
-              "#negoziazione-accessi" id="id30" name=
-              "id30">3.6&nbsp;&nbsp;&nbsp;Negoziazione accessi</a>
+              "#negoziazione-accessi" id="id38" name=
+              "id38">3.6&nbsp;&nbsp;&nbsp;Negoziazione accessi</a>
 
               <ul class="auto-toc">
                 <li><a class="reference internal" href=
-                "#limiti-su-base-ip" id="id31" name=
-                "id31">3.6.1&nbsp;&nbsp;&nbsp;Limiti su base
+                "#limiti-su-base-ip" id="id39" name=
+                "id39">3.6.1&nbsp;&nbsp;&nbsp;Limiti su base
                 ip</a></li>
               </ul>
             </li>
 
             <li>
               <a class="reference internal" href=
-              "#user-authentication" id="id32" name=
-              "id32">3.7&nbsp;&nbsp;&nbsp;User Authentication</a>
+              "#user-authentication" id="id40" name=
+              "id40">3.7&nbsp;&nbsp;&nbsp;User Authentication</a>
 
               <ul class="auto-toc">
                 <li><a class="reference internal" href=
-                "#definire-la-cartella" id="id33" name=
-                "id33">3.7.1&nbsp;&nbsp;&nbsp;Definire la
+                "#definire-la-cartella" id="id41" name=
+                "id41">3.7.1&nbsp;&nbsp;&nbsp;Definire la
                 cartella</a></li>
 
                 <li><a class="reference internal" href=
-                "#creazione-del-database-delle-passwords" id="id34"
-                name="id34">3.7.2&nbsp;&nbsp;&nbsp;Creazione del
+                "#creazione-del-database-delle-passwords" id="id42"
+                name="id42">3.7.2&nbsp;&nbsp;&nbsp;Creazione del
                 database delle passwords</a></li>
 
                 <li><a class="reference internal" href="#id3" id=
-                "id35" name=
-                "id35">3.7.3&nbsp;&nbsp;&nbsp;Configurazione di
+                "id43" name=
+                "id43">3.7.3&nbsp;&nbsp;&nbsp;Configurazione di
                 Apache</a></li>
               </ul>
             </li>
 
             <li><a class="reference internal" href="#cavets" id=
-            "id36" name="id36">3.8&nbsp;&nbsp;&nbsp;Cavets</a></li>
+            "id44" name="id44">3.8&nbsp;&nbsp;&nbsp;Cavets</a></li>
           </ul>
         </li>
 
         <li>
           <a class="reference internal" href="#domain-name-system"
-          id="id37" name="id37">4&nbsp;&nbsp;&nbsp;Domain Name
+          id="id45" name="id45">4&nbsp;&nbsp;&nbsp;Domain Name
           System</a>
 
           <ul class="auto-toc">
             <li><a class="reference internal" href=
-            "#nomi-di-dominio" id="id38" name=
-            "id38">4.1&nbsp;&nbsp;&nbsp;Nomi di dominio</a></li>
+            "#nomi-di-dominio" id="id46" name=
+            "id46">4.1&nbsp;&nbsp;&nbsp;Nomi di dominio</a></li>
 
             <li><a class="reference internal" href=
-            "#tipologie-di-record" id="id39" name=
-            "id39">4.2&nbsp;&nbsp;&nbsp;Tipologie di
+            "#tipologie-di-record" id="id47" name=
+            "id47">4.2&nbsp;&nbsp;&nbsp;Tipologie di
             record</a></li>
 
             <li><a class="reference internal" href="#utilizzo" id=
-            "id40" name=
-            "id40">4.3&nbsp;&nbsp;&nbsp;Utilizzo</a></li>
+            "id48" name=
+            "id48">4.3&nbsp;&nbsp;&nbsp;Utilizzo</a></li>
 
             <li><a class="reference internal" href=
-            "#risoluzione-dei-nomi-di-dominio" id="id41" name=
-            "id41">4.4&nbsp;&nbsp;&nbsp;Risoluzione dei nomi di
+            "#risoluzione-dei-nomi-di-dominio" id="id49" name=
+            "id49">4.4&nbsp;&nbsp;&nbsp;Risoluzione dei nomi di
             dominio</a></li>
 
-            <li><a class="reference internal" href="#dig" id="id42"
-            name="id42">4.5&nbsp;&nbsp;&nbsp;Dig</a></li>
+            <li><a class="reference internal" href="#dig" id="id50"
+            name="id50">4.5&nbsp;&nbsp;&nbsp;Dig</a></li>
           </ul>
         </li>
 
-        <li><a class="reference internal" href="#dnsmasq" id="id43"
-        name="id43">5&nbsp;&nbsp;&nbsp;DNSmasq</a></li>
+        <li><a class="reference internal" href="#dnsmasq" id="id51"
+        name="id51">5&nbsp;&nbsp;&nbsp;DNSmasq</a></li>
 
         <li>
-          <a class="reference internal" href="#samba" id="id44"
-          name="id44">6&nbsp;&nbsp;&nbsp;Samba</a>
+          <a class="reference internal" href="#samba" id="id52"
+          name="id52">6&nbsp;&nbsp;&nbsp;Samba</a>
 
           <ul class="auto-toc">
             <li><a class="reference internal" href="#pacchetti" id=
-            "id45" name=
-            "id45">6.1&nbsp;&nbsp;&nbsp;Pacchetti</a></li>
+            "id53" name=
+            "id53">6.1&nbsp;&nbsp;&nbsp;Pacchetti</a></li>
 
             <li><a class="reference internal" href=
-            "#passwords-e-autenticazione" id="id46" name=
-            "id46">6.2&nbsp;&nbsp;&nbsp;Passwords e
+            "#passwords-e-autenticazione" id="id54" name=
+            "id54">6.2&nbsp;&nbsp;&nbsp;Passwords e
             autenticazione</a></li>
 
             <li><a class="reference internal" href=
-            "#creazione-utenti" id="id47" name=
-            "id47">6.3&nbsp;&nbsp;&nbsp;Creazione Utenti</a></li>
+            "#creazione-utenti" id="id55" name=
+            "id55">6.3&nbsp;&nbsp;&nbsp;Creazione Utenti</a></li>
 
             <li>
               <a class="reference internal" href=
-              "#creare-la-condivisione" id="id48" name=
-              "id48">6.4&nbsp;&nbsp;&nbsp;Creare la
+              "#creare-la-condivisione" id="id56" name=
+              "id56">6.4&nbsp;&nbsp;&nbsp;Creare la
               condivisione</a>
 
               <ul class="auto-toc">
                 <li><a class="reference internal" href=
                 "#sicurezza-permessi-di-esecuzione-sul-server" id=
-                "id49" name=
-                "id49">6.4.1&nbsp;&nbsp;&nbsp;Sicurezza: permessi
+                "id57" name=
+                "id57">6.4.1&nbsp;&nbsp;&nbsp;Sicurezza: permessi
                 di esecuzione sul server</a></li>
               </ul>
             </li>
 
             <li><a class="reference internal" href=
             "#configurazione-dell-applicativo-samba-vero-e-proprio"
-            id="id50" name=
-            "id50">6.5&nbsp;&nbsp;&nbsp;Configurazione
+            id="id58" name=
+            "id58">6.5&nbsp;&nbsp;&nbsp;Configurazione
             dell'applicativo Samba vero e proprio.</a></li>
 
             <li><a class="reference internal" href=
-            "#testare-il-servizio" id="id51" name=
-            "id51">6.6&nbsp;&nbsp;&nbsp;Testare il
+            "#testare-il-servizio" id="id59" name=
+            "id59">6.6&nbsp;&nbsp;&nbsp;Testare il
             Servizio</a></li>
           </ul>
         </li>
 
         <li>
-          <a class="reference internal" href="#firewall" id="id52"
-          name="id52">7&nbsp;&nbsp;&nbsp;Firewall</a>
+          <a class="reference internal" href="#firewall" id="id60"
+          name="id60">7&nbsp;&nbsp;&nbsp;Firewall</a>
 
           <ul class="auto-toc">
             <li><a class="reference internal" href="#links" id=
-            "id53" name="id53">7.1&nbsp;&nbsp;&nbsp;Links</a></li>
+            "id61" name="id61">7.1&nbsp;&nbsp;&nbsp;Links</a></li>
 
             <li><a class="reference internal" href="#ipfilter" id=
-            "id54" name=
-            "id54">7.2&nbsp;&nbsp;&nbsp;Ipfilter</a></li>
+            "id62" name=
+            "id62">7.2&nbsp;&nbsp;&nbsp;Ipfilter</a></li>
 
             <li>
               <a class="reference internal" href=
-              "#progettazione-di-un-firewall" id="id55" name=
-              "id55">7.3&nbsp;&nbsp;&nbsp;Progettazione di un
+              "#progettazione-di-un-firewall" id="id63" name=
+              "id63">7.3&nbsp;&nbsp;&nbsp;Progettazione di un
               firewall</a>
 
               <ul class="auto-toc">
                 <li><a class="reference internal" href=
-                "#collocazione" id="id56" name=
-                "id56">7.3.1&nbsp;&nbsp;&nbsp;Collocazione</a></li>
+                "#collocazione" id="id64" name=
+                "id64">7.3.1&nbsp;&nbsp;&nbsp;Collocazione</a></li>
 
                 <li><a class="reference internal" href=
-                "#policy-di-default" id="id57" name=
-                "id57">7.3.2&nbsp;&nbsp;&nbsp;Policy di
+                "#policy-di-default" id="id65" name=
+                "id65">7.3.2&nbsp;&nbsp;&nbsp;Policy di
                 default</a></li>
 
                 <li><a class="reference internal" href="#hardware"
-                id="id58" name=
-                "id58">7.3.3&nbsp;&nbsp;&nbsp;Hardware</a></li>
+                id="id66" name=
+                "id66">7.3.3&nbsp;&nbsp;&nbsp;Hardware</a></li>
               </ul>
             </li>
 
             <li><a class="reference internal" href=
             "#percorso-dei-pacchetti-tra-tabelle-e-catene" id=
-            "id59" name="id59">7.4&nbsp;&nbsp;&nbsp;Percorso dei
+            "id67" name="id67">7.4&nbsp;&nbsp;&nbsp;Percorso dei
             pacchetti tra tabelle e catene</a></li>
 
             <li>
               <a class="reference internal" href=
-              "#concetti-di-base" id="id60" name=
-              "id60">7.5&nbsp;&nbsp;&nbsp;Concetti di base</a>
+              "#concetti-di-base" id="id68" name=
+              "id68">7.5&nbsp;&nbsp;&nbsp;Concetti di base</a>
 
               <ul class="auto-toc">
                 <li><a class="reference internal" href=
-                "#tabelle-catene-regole" id="id61" name=
-                "id61">7.5.1&nbsp;&nbsp;&nbsp;Tabelle, catene,
+                "#tabelle-catene-regole" id="id69" name=
+                "id69">7.5.1&nbsp;&nbsp;&nbsp;Tabelle, catene,
                 regole</a></li>
 
                 <li><a class="reference internal" href="#match" id=
-                "id62" name=
-                "id62">7.5.2&nbsp;&nbsp;&nbsp;Match</a></li>
+                "id70" name=
+                "id70">7.5.2&nbsp;&nbsp;&nbsp;Match</a></li>
 
                 <li><a class="reference internal" href="#targets"
-                id="id63" name=
-                "id63">7.5.3&nbsp;&nbsp;&nbsp;Targets</a></li>
+                id="id71" name=
+                "id71">7.5.3&nbsp;&nbsp;&nbsp;Targets</a></li>
               </ul>
             </li>
 
             <li><a class="reference internal" href=
-            "#tabella-filter" id="id64" name=
-            "id64">7.6&nbsp;&nbsp;&nbsp;Tabella Filter</a></li>
+            "#tabella-filter" id="id72" name=
+            "id72">7.6&nbsp;&nbsp;&nbsp;Tabella Filter</a></li>
 
             <li><a class="reference internal" href=
-            "#gestione-regole-rules" id="id65" name=
-            "id65">7.7&nbsp;&nbsp;&nbsp;Gestione regole
+            "#flush-automatico-per-macchine-remote" id="id73" name=
+            "id73">7.7&nbsp;&nbsp;&nbsp;Flush automatico per
+            macchine remote</a></li>
+
+            <li><a class="reference internal" href=
+            "#gestione-regole-rules" id="id74" name=
+            "id74">7.8&nbsp;&nbsp;&nbsp;Gestione regole
             (rules)</a></li>
           </ul>
         </li>
 
-        <li><a class="reference internal" href="#note" id="id66"
-        name="id66">8&nbsp;&nbsp;&nbsp;NOTE</a></li>
+        <li><a class="reference internal" href="#note" id="id75"
+        name="id75">8&nbsp;&nbsp;&nbsp;NOTE</a></li>
       </ul>
     </div>
 
@@ -1081,7 +1140,7 @@ deb-src http://volatile.debian.org/debian-volatile Lenny/volatile main
           <p>Questo file contiene le opzioni di apt, come ad
           esempio il proxy:</p>
           <pre class="literal-block">
-Acquire::http::Proxy "http://10.10.208.254:3128"
+Acquire::http::Proxy "http://10.10.208.254:3128";
 </pre>
 
           <p>Si tenga conto che se si imposta un proxy per apt sul
@@ -1095,11 +1154,258 @@ Acquire::http::Proxy "http://10.10.208.254:3128"
     <div class="section" id="squid">
       <h1><a class="toc-backref" href=
       "#id16">2&nbsp;&nbsp;&nbsp;Squid</a></h1>
+
+      <p>Per installare Squid si usino i pacchetti:</p>
+      <pre class="literal-block">
+squid3
+</pre>
+
+      <div class="section" id="configurazione-squid-conf">
+        <h2><a class="toc-backref" href=
+        "#id17">2.1&nbsp;&nbsp;&nbsp;Configurazione:
+        squid.conf</a></h2>
+
+        <p>Segue un estratto del file di configurazione:</p>
+        <pre class="literal-block">
+#TAG: cache_dir (1628)
+#       Usage:
+#
+#       cache_dir Type Directory-Name Fs-specific-data [options]
+#
+#       You can specify multiple cache_dir lines to spread the
+#       cache among different disk partitions.
+#       ...
+#Default:
+# cache_dir ufs /var/spool/squid3 100 16 256
+cache_dir aufs /var/spool/squid3 300 24 256
+#         algoritmo
+#              path della cache
+#                                dimensione in MB
+#                                    directory primo livello
+#                                       secondo livello di directory
+</pre>
+
+        <p>Se si modifica la struttura del filesytem della cache di
+        Squid, ad esempio variando il numero delle directory, puo'
+        essere (ed in genere lo e') opportuno rigenerare la
+        struttura della cache di squid. Tipicamente e' opportuno
+        cancellare la vecchia cache e poi generarne una nuova:</p>
+        <pre class="literal-block">
+# /etc/init.d/squid3 stop
+# rm -r /var/spool/squid3/??
+# squid3 -z
+# /etc/init.d/squid3 start
+</pre>
+
+        <div class="section" id="tag-maximum-object-size">
+          <h3><a class="toc-backref" href=
+          "#id18">2.1.1&nbsp;&nbsp;&nbsp;TAG:
+          maximum_object_size</a></h3>
+
+          <p>Questa direttiva imposta la dimensione massima degli
+          oggetti che vengono slvati sul supporto di storaggio,
+          oggetti di dimensioni superiori verranno scaricati ma non
+          tenuti in cache.</p>
+
+          <p>TAG: maximum_object_size (1760):</p>
+          <pre class="literal-block">
+# TAG: maximum_object_size (1760)
+#       Objects larger than this size will NOT be saved on disk.  The
+#       value is specified in kilobytes, and the default is 4MB.  If
+#       you wish to get a high BYTES hit ratio, you should probably
+#       increase this (one 32 MB object hit counts for 3200 10KB
+#       hits).  If you wish to increase speed more than your want to
+#       save bandwidth you should leave this low.
+#
+#       NOTE: if using the LFUDA replacement policy you should increase
+#       this value to maximize the byte hit rate improvement of LFUDA!
+#       See replacement_policy below for a discussion of this policy.
+#
+#Default:
+# maximum_object_size 4096 KB
+maximum_object_size 150 MB
+</pre>
+        </div>
+
+        <div class="section" id="tag-cache-mem">
+          <h3><a class="toc-backref" href=
+          "#id19">2.1.2&nbsp;&nbsp;&nbsp;TAG: cache_mem</a></h3>
+
+          <p><em>Cache_mem</em> imposta quanta memoria RAM
+          utilizzare per la cache di Squid. Questo dipendera' dalla
+          RAM disponibile sul sistema, e da quanta di questa volete
+          mettere a disposizione di Squid. Questo paramentro
+          influisce sulle prestazioni e sul degrado dei supporti di
+          storaggio (sopratutto se magnetici).</p>
+
+          <p>TAG: cache_mem (1566):</p>
+          <pre class="literal-block">
+#       'cache_mem' specifies the ideal amount of memory to be used
+#       for:
+#               * In-Transit objects
+#               * Hot Objects
+#               * Negative-Cached objects
+#Default:
+# cache_mem 8 M
+cache_mem 100 M
+</pre>
+        </div>
+
+        <div class="section" id="tag-minimum-object-size">
+          <h3><a class="toc-backref" href=
+          "#id20">2.1.3&nbsp;&nbsp;&nbsp;TAG:
+          minimum_object_size</a></h3>
+
+          <p>Questo paramentro imposta la dimensione minima degli
+          oggetti salvati nella cache. Settato a <tt class=
+          "docutils literal"><span class="pre">0</span></tt> o a
+          valori molto piccoli puo' influire negativamente sulla
+          deframmentazione del filesytem e consumare un numero
+          elevato di <em>inode</em>.</p>
+
+          <p>TAG: minimum_object_size:</p>
+          <pre class="literal-block">
+#  TAG: minimum_object_size     (bytes)
+#       Objects smaller than this size will NOT be saved on disk.  The
+#       value is specified in kilobytes, and the default is 0 KB, which
+#       means there is no minimum.
+#
+#Default:
+# minimum_object_size 0 KB
+minimum_object_size 0 KB
+</pre>
+        </div>
+      </div>
+
+      <div class="section" id=
+      "negoziazione-degli-accesi-al-servizio">
+        <h2><a class="toc-backref" href=
+        "#id21">2.2&nbsp;&nbsp;&nbsp;Negoziazione degli accesi al
+        servizio</a></h2>
+
+        <p>Squid e' uno di quei servizi soggetto a problemi di tipo
+        <em>open relay</em>, si deve quindi limitare la rete che
+        puo' accedere al servizio.</p>
+
+        <div class="section" id="acl-e-http-access">
+          <h3><a class="toc-backref" href=
+          "#id22">2.2.1&nbsp;&nbsp;&nbsp;ACL e http access</a></h3>
+
+          <p>Si proceda a creare una <tt class=
+          "docutils literal"><span class="pre">ACL</span></tt> di
+          tipo <tt class="docutils literal"><span class=
+          "pre">src</span></tt> per identificare la lostra rete
+          locale, poi si abiliti l'accesso a questa con la
+          direttiva <tt class="docutils literal"><span class=
+          "pre">http_access</span></tt>. Tutto quanto non e'
+          espressamente autorizzato viene poi negato da un
+          <tt class="docutils literal"><span class=
+          "pre">http_access</span> <span class="pre">deny</span>
+          <span class="pre">all</span></tt> finale.</p>
+          <pre class="literal-block">
+#  TAG: acl
+#       Defining an Access List
+#
+#       Every access list definition must begin with an aclname and acltype,
+#       followed by either type-specific arguments or a quoted filename that
+#       they are read from.
+#       ...
+#       ***** ACL TYPES AVAILABLE *****
+#
+#       acl aclname src ip-address/netmask ...          # clients IP address
+# riga 588
+
+# Example rule allowing access from your local networks.
+# Adapt to list your (internal) IP networks from where browsing
+# should be allowed
+#acl localnet src 10.0.0.0/8    # RFC1918 possible internal network
+#acl localnet src 172.16.0.0/12 # RFC1918 possible internal network
+#acl localnet src 192.168.0.0/16        # RFC1918 possible internal network
+#
+acl localnet src 10.10.208.0/24
+# Riga 606
+#  TAG: http_access
+#       Allowing or Denying access based on defined access lists
+#
+#       Access to the HTTP port:
+#       http_access allow|deny [!]aclname ...
+#
+#       NOTE on default values:
+#
+#       If there are no "access" lines present, the default is to deny
+#       the request.
+
+# Riga 643
+# INSERT YOUR OWN RULE(S) HERE TO ALLOW ACCESS FROM YOUR CLIENTS
+
+# Example rule allowing access from your local networks.
+# Adapt localnet in the ACL section to list your (internal) IP networks
+# from where browsing should be allowed
+#http_access allow localnet
+http_access allow localnet
+</pre>
+        </div>
+      </div>
+
+      <div class="section" id="testare-squid">
+        <h2><a class="toc-backref" href=
+        "#id23">2.3&nbsp;&nbsp;&nbsp;Testare Squid</a></h2>
+
+        <p>Configurato squid e' fondamentale testarne il corretto
+        funzionamento per assicurarsi di non aver creato un
+        <em>open-relay</em>. Per fare dei test significativi serve
+        utilizzare degli host remoti: ci si connetta via ssh a
+        questi per poi utilizzare <tt class=
+        "docutils literal"><span class="pre">wget</span></tt> da
+        riga di comando.</p>
+
+        <div class="section" id="wgetrc">
+          <h3><a class="toc-backref" href=
+          "#id24">2.3.1&nbsp;&nbsp;&nbsp;wgetrc</a></h3>
+
+          <p>Nel file <tt class="docutils literal"><span class=
+          "pre">.wgetrc</span></tt> (si noti il punto iniziale: e'
+          un file nascosto) si puo' impostare il proxy per wget. Si
+          utililizzi l'indirizzo ip del server che si vuole
+          testare, e si seguano i log <tt class=
+          "docutils literal"><span class=
+          "pre">/var/log/squid3/access.log</span></tt> sul
+          server.</p>
+
+          <p>Da notare che la prova va' fatta su una macchina della
+          rete che si vuole testare, non da <em>localhost</em>. Per
+          altro se si utilizzasse <em>direttamente</em> <tt class=
+          "docutils literal"><span class=
+          "pre">localhost</span></tt> non si testerebbe la
+          <em>ACL</em> predisposta, dato che si si rientrerebbe
+          nella ACL (pre-configurata di default) <tt class=
+          "docutils literal"><span class=
+          "pre">localhost</span></tt>.</p>
+
+          <dl class="docutils">
+            <dt>.wgetrc</dt>
+
+            <dd>http_proxy=10.10.208.178:3128</dd>
+          </dl>
+
+          <p>Si proceda a scaricare dal client scelto con un
+          wget:</p>
+          <pre class="literal-block">
+wget http://www.google.it
+</pre>
+
+          <p>Si puo' controllare il corretto funzionamento del
+          server seguendo i log di accesso a Squid:</p>
+          <pre class="literal-block">
+# tail -f /var/log/squid3/access.log
+</pre>
+        </div>
+      </div>
     </div>
 
     <div class="section" id="apache">
       <h1><a class="toc-backref" href=
-      "#id17">3&nbsp;&nbsp;&nbsp;Apache</a></h1>
+      "#id25">3&nbsp;&nbsp;&nbsp;Apache</a></h1>
 
       <p>Apache HTTP Server, o piu' comunemente Apache, e' il nome
       dato alla piattaforma server Web modulare piu' diffusa (ma
@@ -1117,7 +1423,7 @@ Acquire::http::Proxy "http://10.10.208.254:3128"
 
       <div class="section" id="pacchetti-da-installare">
         <h2><a class="toc-backref" href=
-        "#id18">3.1&nbsp;&nbsp;&nbsp;Pacchetti da
+        "#id26">3.1&nbsp;&nbsp;&nbsp;Pacchetti da
         installare::</a></h2>
 
         <blockquote>
@@ -1131,7 +1437,7 @@ Acquire::http::Proxy "http://10.10.208.254:3128"
 
       <div class="section" id="configurazione-di-apache">
         <h2><a class="toc-backref" href=
-        "#id19">3.2&nbsp;&nbsp;&nbsp;Configurazione di
+        "#id27">3.2&nbsp;&nbsp;&nbsp;Configurazione di
         Apache</a></h2>
 
         <p>I file di configurazione di apache si trovano nella
@@ -1190,7 +1496,7 @@ Acquire::http::Proxy "http://10.10.208.254:3128"
 
       <div class="section" id="apache-conf">
         <h2><a class="toc-backref" href=
-        "#id20">3.3&nbsp;&nbsp;&nbsp;apache.conf</a></h2>
+        "#id28">3.3&nbsp;&nbsp;&nbsp;apache.conf</a></h2>
 
         <p>File di configurazione del servizio Apache, contiene le
         impostazioni generiche (ad esempio utilizzo della RAM e
@@ -1247,7 +1553,7 @@ Acquire::http::Proxy "http://10.10.208.254:3128"
 
       <div class="section" id="installazione-di-php">
         <h2><a class="toc-backref" href=
-        "#id21">3.4&nbsp;&nbsp;&nbsp;Installazione di PHP</a></h2>
+        "#id29">3.4&nbsp;&nbsp;&nbsp;Installazione di PHP</a></h2>
 
         <p>Pacchetti da installare: <tt class=
         "docutils literal"><span class="pre">php5</span>
@@ -1255,7 +1561,7 @@ Acquire::http::Proxy "http://10.10.208.254:3128"
 
         <div class="section" id="test-del-modulo-php">
           <h3><a class="toc-backref" href=
-          "#id22">3.4.1&nbsp;&nbsp;&nbsp;Test del modulo
+          "#id30">3.4.1&nbsp;&nbsp;&nbsp;Test del modulo
           php</a></h3>
 
           <p>Creare nella cartella <tt class=
@@ -1285,7 +1591,7 @@ Acquire::http::Proxy "http://10.10.208.254:3128"
         <div class="section" id=
         "installazione-del-supporto-per-mysql">
           <h3><a class="toc-backref" href=
-          "#id23">3.4.2&nbsp;&nbsp;&nbsp;Installazione del supporto
+          "#id31">3.4.2&nbsp;&nbsp;&nbsp;Installazione del supporto
           per Mysql</a></h3>
 
           <p>Installare i pacchetti:</p>
@@ -1302,7 +1608,7 @@ php5-mysql phpmyadmin
 
         <div class="section" id="phpmyadmin">
           <h3><a class="toc-backref" href=
-          "#id24">3.4.3&nbsp;&nbsp;&nbsp;phpmyadmin</a></h3>
+          "#id32">3.4.3&nbsp;&nbsp;&nbsp;phpmyadmin</a></h3>
 
           <p>L'interfaccia web Phpmyadmin non richede
           necessariamente la presenza di un database Mysql locale,
@@ -1327,7 +1633,7 @@ php5-mysql phpmyadmin
         <div class="section" id=
         "installazione-del-supporto-per-postgresql">
           <h3><a class="toc-backref" href=
-          "#id25">3.4.4&nbsp;&nbsp;&nbsp;Installazione del supporto
+          "#id33">3.4.4&nbsp;&nbsp;&nbsp;Installazione del supporto
           per Postgresql</a></h3>
 
           <p>Installare i pacchetti:</p>
@@ -1344,7 +1650,7 @@ php5-pgsql phppgadmin
 
         <div class="section" id="phppgadmin">
           <h3><a class="toc-backref" href=
-          "#id26">3.4.5&nbsp;&nbsp;&nbsp;phppgadmin</a></h3>
+          "#id34">3.4.5&nbsp;&nbsp;&nbsp;phppgadmin</a></h3>
 
           <p>L'interfaccia web Phppgadmin per il database server
           PostgreSQL non richede necessariamente la presenza di un
@@ -1369,7 +1675,7 @@ php5-pgsql phppgadmin
 
       <div class="section" id="virtual-hosts">
         <h2><a class="toc-backref" href=
-        "#id27">3.5&nbsp;&nbsp;&nbsp;Virtual hosts</a></h2>
+        "#id35">3.5&nbsp;&nbsp;&nbsp;Virtual hosts</a></h2>
 
         <blockquote>
           <ul class="simple">
@@ -1410,7 +1716,7 @@ php5-pgsql phppgadmin
 
         <div class="section" id="gestione-dns">
           <h3><a class="toc-backref" href=
-          "#id28">3.5.1&nbsp;&nbsp;&nbsp;Gestione DNS</a></h3>
+          "#id36">3.5.1&nbsp;&nbsp;&nbsp;Gestione DNS</a></h3>
 
           <p>Prima di tutto per poter impostare i virtual hosts
           dovete avere un server DNS che risolva i vostri nomi di
@@ -1493,7 +1799,7 @@ php5-pgsql phppgadmin
 
         <div class="section" id="virtual-host">
           <h3><a class="toc-backref" href=
-          "#id29">3.5.2&nbsp;&nbsp;&nbsp;Virtual host</a></h3>
+          "#id37">3.5.2&nbsp;&nbsp;&nbsp;Virtual host</a></h3>
 
           <p>Esempio di Virtual host:</p>
           <pre class="literal-block">
@@ -1605,7 +1911,7 @@ php5-pgsql phppgadmin
 
       <div class="section" id="negoziazione-accessi">
         <h2><a class="toc-backref" href=
-        "#id30">3.6&nbsp;&nbsp;&nbsp;Negoziazione accessi</a></h2>
+        "#id38">3.6&nbsp;&nbsp;&nbsp;Negoziazione accessi</a></h2>
 
         <p>Tipicamente quando si installa un server web il proprio
         desiderio e' di dare accesso ai materiali disponibili al
@@ -1618,7 +1924,7 @@ php5-pgsql phppgadmin
 
         <div class="section" id="limiti-su-base-ip">
           <h3><a class="toc-backref" href=
-          "#id31">3.6.1&nbsp;&nbsp;&nbsp;Limiti su base ip</a></h3>
+          "#id39">3.6.1&nbsp;&nbsp;&nbsp;Limiti su base ip</a></h3>
 
           <p>La forma piu' semplice di restrizine degli accessi e'
           su base degli indirizzi IP dei client: tipicamente i siti
@@ -1673,7 +1979,7 @@ php5-pgsql phppgadmin
 
       <div class="section" id="user-authentication">
         <h2><a class="toc-backref" href=
-        "#id32">3.7&nbsp;&nbsp;&nbsp;User Authentication</a></h2>
+        "#id40">3.7&nbsp;&nbsp;&nbsp;User Authentication</a></h2>
 
         <p>A volte conviene negoziare gli accessi ad un area di un
         sito tramite autenticazione basata sull'accopiata <em>nome
@@ -1690,7 +1996,7 @@ php5-pgsql phppgadmin
 
         <div class="section" id="definire-la-cartella">
           <h3><a class="toc-backref" href=
-          "#id33">3.7.1&nbsp;&nbsp;&nbsp;Definire la
+          "#id41">3.7.1&nbsp;&nbsp;&nbsp;Definire la
           cartella</a></h3>
 
           <p>Decidere quale sara' il <em>path</em> della cartella
@@ -1707,7 +2013,7 @@ php5-pgsql phppgadmin
         <div class="section" id=
         "creazione-del-database-delle-passwords">
           <h3><a class="toc-backref" href=
-          "#id34">3.7.2&nbsp;&nbsp;&nbsp;Creazione del database
+          "#id42">3.7.2&nbsp;&nbsp;&nbsp;Creazione del database
           delle passwords</a></h3>
 
           <p>Un modo semplice per gestire una database di
@@ -1745,7 +2051,7 @@ htpasswd -c /home/utente/passwords luca
 
         <div class="section" id="id3">
           <h3><a class="toc-backref" href=
-          "#id35">3.7.3&nbsp;&nbsp;&nbsp;Configurazione di
+          "#id43">3.7.3&nbsp;&nbsp;&nbsp;Configurazione di
           Apache</a></h3>
 
           <p>Ora possiamo passare alla configurazione vera e
@@ -1820,7 +2126,7 @@ require valid-user
 
       <div class="section" id="cavets">
         <h2><a class="toc-backref" href=
-        "#id36">3.8&nbsp;&nbsp;&nbsp;Cavets</a></h2>
+        "#id44">3.8&nbsp;&nbsp;&nbsp;Cavets</a></h2>
 
         <p>Problemi di cache:</p>
 
@@ -1845,7 +2151,7 @@ require valid-user
 
     <div class="section" id="domain-name-system">
       <h1><a class="toc-backref" href=
-      "#id37">4&nbsp;&nbsp;&nbsp;Domain Name System</a></h1>
+      "#id45">4&nbsp;&nbsp;&nbsp;Domain Name System</a></h1>
 
       <p>Domain Name System (spesso indicato con DNS) e' un
       servizio utilizzato per la risoluzione di nomi di host in
@@ -1870,7 +2176,7 @@ require valid-user
 
       <div class="section" id="nomi-di-dominio">
         <h2><a class="toc-backref" href=
-        "#id38">4.1&nbsp;&nbsp;&nbsp;Nomi di dominio</a></h2>
+        "#id46">4.1&nbsp;&nbsp;&nbsp;Nomi di dominio</a></h2>
 
         <p>Un nome a dominio e' costituito da una serie di stringhe
         separate da punti, ad esempio it.wikipedia.org. A
@@ -1892,7 +2198,7 @@ require valid-user
 
       <div class="section" id="tipologie-di-record">
         <h2><a class="toc-backref" href=
-        "#id39">4.2&nbsp;&nbsp;&nbsp;Tipologie di record</a></h2>
+        "#id47">4.2&nbsp;&nbsp;&nbsp;Tipologie di record</a></h2>
 
         <p>Ad un nome DNS possono corrispondere diversi tipi di
         informazioni. Per questo motivo, esistono diversi tipi di
@@ -1947,7 +2253,7 @@ require valid-user
 
       <div class="section" id="utilizzo">
         <h2><a class="toc-backref" href=
-        "#id40">4.3&nbsp;&nbsp;&nbsp;Utilizzo</a></h2>
+        "#id48">4.3&nbsp;&nbsp;&nbsp;Utilizzo</a></h2>
 
         <p>I computer vengono identificati in rete grazie agli
         indirizzi <em>IP</em>, questi pero' non sono comodi per gli
@@ -1964,7 +2270,7 @@ PING www.l.google.com (74.125.43.104) 56(84) bytes of data.
 
       <div class="section" id="risoluzione-dei-nomi-di-dominio">
         <h2><a class="toc-backref" href=
-        "#id41">4.4&nbsp;&nbsp;&nbsp;Risoluzione dei nomi di
+        "#id49">4.4&nbsp;&nbsp;&nbsp;Risoluzione dei nomi di
         dominio</a></h2>
 
         <p>Ci sono vari strumenti per interrogare i server DNS e
@@ -2029,7 +2335,7 @@ ns4.mydomain.com.       96208   IN      A       63.251.83.74
 
       <div class="section" id="dig">
         <h2><a class="toc-backref" href=
-        "#id42">4.5&nbsp;&nbsp;&nbsp;Dig</a></h2>
+        "#id50">4.5&nbsp;&nbsp;&nbsp;Dig</a></h2>
 
         <p>Vediamo alcune opzioni utili nell'utilizzo di <tt class=
         "docutils literal"><span class="pre">dig</span></tt> per
@@ -2106,7 +2412,7 @@ l.google.com.           80856   IN      NS      g.l.google.com.
 
     <div class="section" id="dnsmasq">
       <h1><a class="toc-backref" href=
-      "#id43">5&nbsp;&nbsp;&nbsp;DNSmasq</a></h1>
+      "#id51">5&nbsp;&nbsp;&nbsp;DNSmasq</a></h1>
 
       <p>Dnsmasq puo' svolgere le funzioni di un DNS cache /
       forwarder e un server DHCP caratterizzato dalla facilita' di
@@ -2145,7 +2451,7 @@ l.google.com.           80856   IN      NS      g.l.google.com.
 
     <div class="section" id="samba">
       <h1><a class="toc-backref" href=
-      "#id44">6&nbsp;&nbsp;&nbsp;Samba</a></h1>
+      "#id52">6&nbsp;&nbsp;&nbsp;Samba</a></h1>
 
       <p>Samba e' un progetto libero che fornisce servizi di
       condivisione di file e stampanti a client SMB/CIFS.</p>
@@ -2166,7 +2472,7 @@ l.google.com.           80856   IN      NS      g.l.google.com.
 
       <div class="section" id="pacchetti">
         <h2><a class="toc-backref" href=
-        "#id45">6.1&nbsp;&nbsp;&nbsp;Pacchetti</a></h2>
+        "#id53">6.1&nbsp;&nbsp;&nbsp;Pacchetti</a></h2>
 
         <p>Pacchetti da installare per utilizzare Samba in
         modalita' client <a class="footnote-reference" href="#id5"
@@ -2219,7 +2525,7 @@ dpkg-reconfigure samba-common
 
       <div class="section" id="passwords-e-autenticazione">
         <h2><a class="toc-backref" href=
-        "#id46">6.2&nbsp;&nbsp;&nbsp;Passwords e
+        "#id54">6.2&nbsp;&nbsp;&nbsp;Passwords e
         autenticazione</a></h2>
 
         <p>Per poter configurare Samba in modo che usi un sistema
@@ -2280,7 +2586,7 @@ dpkg-reconfigure samba-common
 
       <div class="section" id="creazione-utenti">
         <h2><a class="toc-backref" href=
-        "#id47">6.3&nbsp;&nbsp;&nbsp;Creazione Utenti</a></h2>
+        "#id55">6.3&nbsp;&nbsp;&nbsp;Creazione Utenti</a></h2>
 
         <p>Creiamo per primo l'utente sotto GNU/Linux, facendo
         attenzione a <em>non dargli una shell di sistema</em>. Gli
@@ -2317,7 +2623,7 @@ smbpasswd  sambo
 
       <div class="section" id="creare-la-condivisione">
         <h2><a class="toc-backref" href=
-        "#id48">6.4&nbsp;&nbsp;&nbsp;Creare la
+        "#id56">6.4&nbsp;&nbsp;&nbsp;Creare la
         condivisione</a></h2>
 
         <p>La condivisione altro non e' che una cartella sul server
@@ -2344,7 +2650,7 @@ smbpasswd  sambo
         <div class="section" id=
         "sicurezza-permessi-di-esecuzione-sul-server">
           <h3><a class="toc-backref" href=
-          "#id49">6.4.1&nbsp;&nbsp;&nbsp;Sicurezza: permessi di
+          "#id57">6.4.1&nbsp;&nbsp;&nbsp;Sicurezza: permessi di
           esecuzione sul server</a></h3>
 
           <p>Bisognerebbe notare sul server i permessi di
@@ -2374,7 +2680,7 @@ smbpasswd  sambo
       <div class="section" id=
       "configurazione-dell-applicativo-samba-vero-e-proprio">
         <h2><a class="toc-backref" href=
-        "#id50">6.5&nbsp;&nbsp;&nbsp;Configurazione
+        "#id58">6.5&nbsp;&nbsp;&nbsp;Configurazione
         dell'applicativo Samba vero e proprio.</a></h2>
 
         <p>Avendo preparato gli utenti (ancora una volta: non si
@@ -2414,7 +2720,7 @@ smbpasswd  sambo
 
       <div class="section" id="testare-il-servizio">
         <h2><a class="toc-backref" href=
-        "#id51">6.6&nbsp;&nbsp;&nbsp;Testare il Servizio</a></h2>
+        "#id59">6.6&nbsp;&nbsp;&nbsp;Testare il Servizio</a></h2>
 
         <p>Come testare il servizio</p>
 
@@ -2454,7 +2760,7 @@ mount -t smbfs //localhost/sambo_share /mnt/sambo_mount/ --verbose -o user=sambo
 
     <div class="section" id="firewall">
       <h1><a class="toc-backref" href=
-      "#id52">7&nbsp;&nbsp;&nbsp;Firewall</a></h1>
+      "#id60">7&nbsp;&nbsp;&nbsp;Firewall</a></h1>
 
       <p>In Informatica, nell'ambito delle reti di computer, un
       firewall (termine inglese dal significato originario di
@@ -2504,7 +2810,7 @@ mount -t smbfs //localhost/sambo_share /mnt/sambo_mount/ --verbose -o user=sambo
 
       <div class="section" id="links">
         <h2><a class="toc-backref" href=
-        "#id53">7.1&nbsp;&nbsp;&nbsp;Links</a></h2>
+        "#id61">7.1&nbsp;&nbsp;&nbsp;Links</a></h2>
 
         <ul class="simple">
           <li><a class="reference external" href=
@@ -2518,7 +2824,7 @@ mount -t smbfs //localhost/sambo_share /mnt/sambo_mount/ --verbose -o user=sambo
 
       <div class="section" id="ipfilter">
         <h2><a class="toc-backref" href=
-        "#id54">7.2&nbsp;&nbsp;&nbsp;Ipfilter</a></h2>
+        "#id62">7.2&nbsp;&nbsp;&nbsp;Ipfilter</a></h2>
 
         <p>Link: <a class="reference external" href=
         "http://iptables-tutorial.frozentux.net/iptables-tutorial.html#IPFILTERING">
@@ -2554,7 +2860,7 @@ mount -t smbfs //localhost/sambo_share /mnt/sambo_mount/ --verbose -o user=sambo
 
       <div class="section" id="progettazione-di-un-firewall">
         <h2><a class="toc-backref" href=
-        "#id55">7.3&nbsp;&nbsp;&nbsp;Progettazione di un
+        "#id63">7.3&nbsp;&nbsp;&nbsp;Progettazione di un
         firewall</a></h2>
 
         <p>Per implementare un firewall bisogna decidere un aio di
@@ -2563,7 +2869,7 @@ mount -t smbfs //localhost/sambo_share /mnt/sambo_mount/ --verbose -o user=sambo
 
         <div class="section" id="collocazione">
           <h3><a class="toc-backref" href=
-          "#id56">7.3.1&nbsp;&nbsp;&nbsp;Collocazione</a></h3>
+          "#id64">7.3.1&nbsp;&nbsp;&nbsp;Collocazione</a></h3>
 
           <p>DMZ e MZ, internet, intranet, extranet. Frammentazione
           della rete, decidere se diversi reparti di una azienda si
@@ -2595,7 +2901,7 @@ mount -t smbfs //localhost/sambo_share /mnt/sambo_mount/ --verbose -o user=sambo
 
         <div class="section" id="policy-di-default">
           <h3><a class="toc-backref" href=
-          "#id57">7.3.2&nbsp;&nbsp;&nbsp;Policy di default</a></h3>
+          "#id65">7.3.2&nbsp;&nbsp;&nbsp;Policy di default</a></h3>
 
           <p>Drop o Accept: conseguenze per sicurezza, facilita' di
           gestione.</p>
@@ -2603,7 +2909,7 @@ mount -t smbfs //localhost/sambo_share /mnt/sambo_mount/ --verbose -o user=sambo
 
         <div class="section" id="hardware">
           <h3><a class="toc-backref" href=
-          "#id58">7.3.3&nbsp;&nbsp;&nbsp;Hardware</a></h3>
+          "#id66">7.3.3&nbsp;&nbsp;&nbsp;Hardware</a></h3>
 
           <p>Sostanzialmente potremmo distinquere due tipologie di
           hardware:</p>
@@ -2631,7 +2937,7 @@ mount -t smbfs //localhost/sambo_share /mnt/sambo_mount/ --verbose -o user=sambo
       <div class="section" id=
       "percorso-dei-pacchetti-tra-tabelle-e-catene">
         <h2><a class="toc-backref" href=
-        "#id59">7.4&nbsp;&nbsp;&nbsp;Percorso dei pacchetti tra
+        "#id67">7.4&nbsp;&nbsp;&nbsp;Percorso dei pacchetti tra
         tabelle e catene</a></h2>
 
         <p>link: <a class="reference external" href=
@@ -2641,11 +2947,11 @@ mount -t smbfs //localhost/sambo_share /mnt/sambo_mount/ --verbose -o user=sambo
 
       <div class="section" id="concetti-di-base">
         <h2><a class="toc-backref" href=
-        "#id60">7.5&nbsp;&nbsp;&nbsp;Concetti di base</a></h2>
+        "#id68">7.5&nbsp;&nbsp;&nbsp;Concetti di base</a></h2>
 
         <div class="section" id="tabelle-catene-regole">
           <h3><a class="toc-backref" href=
-          "#id61">7.5.1&nbsp;&nbsp;&nbsp;Tabelle, catene,
+          "#id69">7.5.1&nbsp;&nbsp;&nbsp;Tabelle, catene,
           regole</a></h3>
 
           <p>Iptables lavora su 3 tabelle (tables) di default:</p>
@@ -2672,7 +2978,7 @@ mount -t smbfs //localhost/sambo_share /mnt/sambo_mount/ --verbose -o user=sambo
 
         <div class="section" id="match">
           <h3><a class="toc-backref" href=
-          "#id62">7.5.2&nbsp;&nbsp;&nbsp;Match</a></h3>
+          "#id70">7.5.2&nbsp;&nbsp;&nbsp;Match</a></h3>
 
           <p>I Match di una regola (rule) servono a testare un
           pacchetto per valutare se corrisponda a certe
@@ -2724,7 +3030,7 @@ mount -t smbfs //localhost/sambo_share /mnt/sambo_mount/ --verbose -o user=sambo
 
         <div class="section" id="targets">
           <h3><a class="toc-backref" href=
-          "#id63">7.5.3&nbsp;&nbsp;&nbsp;Targets</a></h3>
+          "#id71">7.5.3&nbsp;&nbsp;&nbsp;Targets</a></h3>
 
           <p>Se un pacchetto soddisfa le condizioni del Match
           <em>salta</em> (jump) su uno dei target possibili, in
@@ -2853,7 +3159,7 @@ mount -t smbfs //localhost/sambo_share /mnt/sambo_mount/ --verbose -o user=sambo
 
       <div class="section" id="tabella-filter">
         <h2><a class="toc-backref" href=
-        "#id64">7.6&nbsp;&nbsp;&nbsp;Tabella Filter</a></h2>
+        "#id72">7.6&nbsp;&nbsp;&nbsp;Tabella Filter</a></h2>
 
         <p>E' quella implicita e predefinita (-t filter) Riguarda
         le attivitÃ&nbsp; di filtraggio del traffico. Ha 3 catene
@@ -2874,9 +3180,37 @@ mount -t smbfs //localhost/sambo_share /mnt/sambo_mount/ --verbose -o user=sambo
         -j ACCEPT</p>
       </div>
 
+      <div class="section" id=
+      "flush-automatico-per-macchine-remote">
+        <h2><a class="toc-backref" href=
+        "#id73">7.7&nbsp;&nbsp;&nbsp;Flush automatico per macchine
+        remote</a></h2>
+
+        <p>Se state provando una configurazione del firewall per
+        una macchina remota e' buona norma per evitare brutte
+        figure attivare uno script che faccia il <em>flush</em>
+        delle regole dopo qualche minuto. Potreste infatti
+        inavvertitamente impostare una regola che vi impedisca di
+        raggiungere la macchina remota, cosi' da non poter neanche
+        eliminare quella regola e ripristinare la situazioe
+        precedente.</p>
+
+        <p><em>Veramnete</em>, prima di lavorare sul firewall di
+        una macchina remota inpostate almeno un <tt class=
+        "docutils literal"><span class="pre">at</span> <span class=
+        "pre">now</span> <span class="pre">+5</span> <span class=
+        "pre">min</span></tt> o con un'oretta di margine per fare
+        il <em>flush</em> delle regole (su tutte le tabelle):</p>
+        <pre class="literal-block">
+    at now +5 min
+at&gt; /sbin/iptables -F
+at&gt; [CTR+d]
+</pre>
+      </div>
+
       <div class="section" id="gestione-regole-rules">
         <h2><a class="toc-backref" href=
-        "#id65">7.7&nbsp;&nbsp;&nbsp;Gestione regole
+        "#id74">7.8&nbsp;&nbsp;&nbsp;Gestione regole
         (rules)</a></h2>
 
         <p>Il comando iptables viene usato per ogni attivitÃ&nbsp;
@@ -2944,7 +3278,7 @@ mount -t smbfs //localhost/sambo_share /mnt/sambo_mount/ --verbose -o user=sambo
 
     <div class="section" id="note">
       <h1><a class="toc-backref" href=
-      "#id66">8&nbsp;&nbsp;&nbsp;NOTE</a></h1>
+      "#id75">8&nbsp;&nbsp;&nbsp;NOTE</a></h1>
 
       <ul class="simple">
         <li>controllare apache</li>