Martin Mulder wrote:
Hi,
I have (maybee a stupid) question.
I have an apache server as reverse proxy, squid as caching server and
Zope/Plone as backend servers.
Senario:
1) Apache gets a request for my.domain.com
2) Apache does a ProxyPass to my balancer
3) I have 2 "sticky" vhosts in apache which are the balancer members.
These are not reachable from the outside, and are called sticky1 and
sticky2.
These "sticky" vhost creates a cookie, which is uses by the balancer,
to decide the sticky server.
these sticky vhost forwards the request to Squid.
4) Squid is running @ 127.0.0.1:3389 and 127.0.0.2:3389
5) Sticky1 vhost proxies a request to http://sticky1.domain.com:3389,
sticky2 vhost proxies a request to http://sticky2.domain.com:3389
( where sticky1.domain.com resolves to 127.0.0.1 and sticky2.domain.com
resolves to 127.0.0.2 )
At the moment I have the following configuration:
## Backend server 1
cache_peer 192.168.2.3 parent 8100 0 no-query originserver
name=server1
cache_peer_domain server1 sticky1.domain.com
## Backend server 2
cache_peer 192.168.2.4 parent 8100 0 no-query originserver
name=server2
cache_peer_domain server2 sticky2.domain.com
This results in:
a webrequest comes to apache ( without an host-cookie ) on
my.domain.com
the request will be proxied to a balancermember ( based on the
balancing policy )
this vhost creates a cookie ( like: BALANCEID: balancer.sticky1 or
BALANCEID: balancer.sticky2 )
the vhosts proxied the request to http://sticky1.domain.com:3389 or
http://sticky2.domain.com:3389
-- The request reaches squid --
the request comes to the cache_peer depending on the domain ( sticky1
of sticky2 )
squid delivers the page ( or from cache, or from originserver )
In this case squid can deliver a 500 or 503 if the requested backend
server is down.
So if my request has a cookie for sticky1.domain.com and 192.168.2.3
originserver is down, the users with this cookie get an error.
So if my request has a cookie for sticky2.domain.com and 192.168.2.4
originserver is down, the users with this cookie get an error.
What I try, but can't get working:
every cache_peer_domain has 2 cache_peers:
* name= is a unique identifier. It cannot be used twice.
## Backend server 1
cache_peer 192.168.2.3 parent 8100 0 no-query originserver
name=server1
cache_peer 192.168.2.4 parent 8100 0 no-query originserver name=server2
// This server doesn't have the session information
cache_peer_domain server1 sticky1.domain.com
## Backend server 2
cache_peer 192.168.2.4 parent 8100 0 no-query originserver
name=server2
cache_peer 192.168.2.3 parent 8100 0 no-query originserver name=server1
// This server doesn't have the session information
cache_peer_domain server2 sticky2.domain.com
But the cache peer which hasn't the session may only be used it the
other cache_peer is down.
is the possible with squid 2.6?
Not the way you are trying.
Assuming that the use of cookies means the visitors need to always
request from the same origin.
I think the simpler approach you need is to have Squid as front-end
accelerator using sourcehash to load balance over the real origin servers.
Amos
--
Please be using
Current Stable Squid 2.7.STABLE5 or 3.0.STABLE10
Current Beta Squid 3.1.0.2
