Re: Running 2 Squid Caches

A.Sharaz@ucc.hull.ac.uk writes:

>Hi,
>
>Having just upgraded to Squid 1.0.10, I'd now like to try running 2 squid
>caches on site. Am I naive in assuming that all I've got to do is:-
>1). Set up our DNS so that
>
>a). wwcache.hull.ac.uk has two "A" entries pointing to the 2 caches. Assuming
>that the DNS works correctly, a query on wwwcache.hull.ac.uk should return
>alternate IP addresses (?)
>
>b). Set up entries for the 2 caches ( wwwcache1.hull.ac.uk and
>wwwcache2.hull.ac.uk)
>
>2). Configure our 2 squid.conf files to know about each other
>
>On cache 1 set up cache_host wwwcache2.hull.ac.uk neighbor 3128 3130 proxy-onl
y
>On cache 2 set up cache_host wwwcache1.hull.ac.uk neoghbor 3128 3130 proxy-onl
y

Looks good...

>{ Possibly use the weight=n option to get each cache to check the other one
>first before tryong other cache_host entries?)

The wieghts don't have any effect for neighbour (sibling) caches, only
parents.

>W.R.T.a remote site config, would they just keep
>wwwcache.hull.ac.uk ..... and rely on our caches checking with each other or
>would they have to put both wwwcache1 and wwwcache2 in their config file?

wwwcache1 and wwwcache2 will not query each other until there is
a HTTP request at one of them. In other words, receving an ICP query
at one of your caches will not cause an ICP query to the other. If you
want remote sites to query both caches, they will need to list both
in their config file.

>
>Does the above sound correct? Have I missed something out? any thoughts /
>comment would be appreciated.

The only other arrangement you might consider is to make one a parent
for the other, but the other a neighbour for the first, e.gg:

on wwwcache2:
    cache_host wwwcache1.hull.ac.uk parent ...

on wwwcache1:
    cache_host wwwcache2.hull.ac.uk neighbor ...

Then wwwcache1 would in theory contain everything that wwwcache2 contains
but not necessarily the other way around. Then your neighbors could
just ping wwwcache1. This may not make much sense, depending on what
is your motivation for having two caches.

Duane W.
Received on Wed Aug 28 1996 - 09:06:43 MDT