– Compile and install 3.1.x version of squid.

# useradd -d /opt/squid squid

# wget http://www.squid-cache.org/Versions/v3/3.1/squid-3.1.11-20110228.tar.gz

# tar xvzf squid-3.1.11-20110228.tar.gz

# cd squid-3.1.11-20110228; ./configure –prefix=/opt/squid/

# make; make install

# /opt/squid/sbin/squid -z

Configure squid

edit /opt/squid/etc/squid.conf

cache_effective_user squid

acl manager proto cache_object
acl localhost src 127.0.0.1/32 ::1
acl to_localhost dst 127.0.0.0/8 0.0.0.0/32 ::1

acl to_ipv6 dst ipv6
http_access allow to_ipv6 !all
tcp_outgoing_address 2001:: to_ipv6
tcp_outgoing_address 12.34.56.78 !to_ipv6

And add necessary acls to allow access for your network to squid.

Testing:

$ telnet <v6_address> 3128
Trying 2001::…
Connected to 2001::..
Escape character is ‘^]’.
get http://ipv6.google.com/
HTTP/1.0 200 OK

Check the access.log to make sure

1298965141.719    477 2001:: TCP_MISS/200 25918 GET http://ipv6.google.com/ – DIRECT/2a00:1450:8002::6a text/html