We are currently looking up upgrade our squid servers from 2.5 to 2.6 or higher. In our current configuration, we send requests to the origin servers to a single IP address that points to a load balancer which is associated with a pool of web servers. In 2.5, this is easy to do with the httpd_accel_* directives, but in 2.6 I know that those directives have been replaced by the http_port directive with accel, vhost, vport, etc. options. I have supplied the squid.conf we are attempting to use below with a build of 2.6. With this configuration, it appears that any connection attempt that doesn't get a cache hit resolves the virtual host, and makes an HTTP connection to that resolved public IP instead sending the request to the internal 10.x.x.11 address.
Is there a way under squid 2.6 and higher to force any request that doesn't make a cache hit to a single backend IP address? The vhost option is necessary with http_port since the Host: header must contain the Virtual Host name as our web servers use that data to determine what which site to serve.
squid build:
# /opt/squid-2.6.16/sbin/squid -v
Squid Cache: Version 2.6.STABLE16
configure options: '--prefix=/opt/squid-2.6.16' '--enable-async-io' '--enable-snmp' '--enable-removal-policies=heap' '--enable-referer-log' '--enable-useragent-log'
----- squid.conf -----
acl snmppublic snmp_community local-squid-ro
acl all src 0.0.0.0/0.0.0.0
acl manager proto cache_object
acl localhost src 127.0.0.1/255.255.255.255
acl to_localhost dst 127.0.0.0/8
acl local_network src 172.16.0.0/16 10.0.0.0/8
acl SSL_ports port 443
acl Safe_ports port 80 # http
acl Safe_ports port 21 # ftp
acl Safe_ports port 443 # https
acl Safe_ports port 70 # gopher
acl Safe_ports port 210 # wais
acl Safe_ports port 1025-65535 # unregistered ports
acl Safe_ports port 280 # http-mgmt
acl Safe_ports port 488 # gss-http
acl Safe_ports port 591 # filemaker
acl Safe_ports port 777 # multiling http
acl CONNECT method CONNECT
http_access allow manager localhost
http_access deny manager
http_access deny !Safe_ports
http_access deny CONNECT !SSL_ports
acl web_ports port 80
http_access allow web_ports
http_access allow manager localhost
http_access allow manager local_network
http_access deny manager
acl purge method PURGE
http_access allow purge localhost
http_access allow purge local_network
http_access deny purge
http_access allow all
icp_access allow all
http_port 80 accel defaultsite=10.x.x.11 vhost
cache_peer 10.x.x.11 parent 80 0 no-query originserver
hierarchy_stoplist cgi-bin ?
acl QUERY urlpath_regex cgi-bin \?
cache deny QUERY
memory_replacement_policy heap LFUDA
cache_replacement_policy heap LFUDA
logformat CustomLog %>a %ui %un [%{%d/%b/%Y:%H:%M:%S %z}tl] "%rm %ru HTTP/%rv" %Hs %<st "%{Referer}>h" "%{User-Agent}>h" "%{Cookie}>h" %Ss:%Sh
access_log /opt/squid-2.6.16/var/logs/custom.log CustomLog
refresh_pattern ^ftp: 1440 20% 10080
refresh_pattern ^gopher: 1440 0% 1440
refresh_pattern . 0 20% 4320
acl apache rep_header Server ^Apache
broken_vary_encoding allow apache
cache_effective_user www
cache_effective_group www
visible_hostname squid.domain.com
Regards,
Russell
