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<p class="MsoNormal">Hello,<o:p></o:p></p>
<p class="MsoNormal"><span lang="EN-US">I need to definitively solve the ipv6 (un)reachbility issue.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">I state I read this topic: <a href="http://squid-web-proxy-cache.1019090.n4.nabble.com/dns-v4-first-on-ignored-td4658427.html">
http://squid-web-proxy-cache.1019090.n4.nabble.com/dns-v4-first-on-ignored-td4658427.html</a> but not found a solution. Amos wrote “Squid tests for IPv6 ability automatically by opening a socket on a private IP address, if that works the socket options are
noted and used.”<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Anyway I disable IPv6 on my Red Hat 7.4 with the following:<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">net.ipv6.conf.all.disable_ipv6 = 1<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">net.ipv6.conf.default.disable_ipv6 = 1<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">net.ipv6.conf.bond0.disable_ipv6 = 1<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">net.ipv6.conf.lo.disable_ipv6 = 1<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Used the “dns_v4_first on” and also “tcp_outgoing_address 172.31.1.x all” on squid conf to force the use of IPv4.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Anyway squid try to connect to the IPv6 address instead of IPv4 and I’m not able to reach it:<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">C:\Users\atroiano>nslookup download.pdfforge.org<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Server: espevmdxxxx.xxxx.prv<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Address: 172.x.x.x<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal">Risposta da un server non autorevole:<o:p></o:p></p>
<p class="MsoNormal"><span lang="EN-US">Nome: download.pdfforge.org<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Addresses: 2001:4860:4802:38::15<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> 2001:4860:4802:34::15<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> 2001:4860:4802:32::15<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> 2001:4860:4802:36::15<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> 216.239.32.21<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> 216.239.38.21<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> 216.239.36.21<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"> 216.239.34.21<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">[root@HUB-RM-PRX-03 ~]# tail -f /var/log/squid/rsa/access.log | grep pdfforge.org<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">%SQUID-4: 172.31.x.x 49444 [25/Jan/2019:11:02:58 +0100] "GET http://download.pdfforge.org/download/pdfcreator/PDFCreator-stable HTTP/1.1" download.pdfforge.org - - "/download/pdfcreator/PDFCreator-stable" 503 text/html
4545 "-" "Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:64.0) Gecko/20100101 Firefox/64.0" TCP_MISS:HIER_DIRECT 2001:4860:4802:38::15 80 0<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Squid doesn’t try to connect to IPv4 addresses for this site and for many others.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">What can I do?<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">My ISP is IPv4 only.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Thank you, Regards.<o:p></o:p></span></p>
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