Cache digests

I'm sure this is my oversight and not a squid one. But...

I have two caches with a round-robin DNS sharing the workload of
wwwcache.cf.ac.uk between the two. Last week I upgraded one of the pair to
squid 2.1 so it has the ability to publish cache digests. The other one is
still running squid 1.x so can't.

One of my neighbours has made a TCP request for a URL from the 1.x cache
without sending an ICP query first. Is it possible that it had fetched a
cache digest from the other cache and got confused as to where it should
request the document from ? The DNS set up looks like

wwwcache.cf.ac.uk A 131.251.0.11
wwwcache.cf.ac.uk A 131.251.0.8

11.0.251.131 PTR mnementh.cf.ac.uk
8.0.251.131 PTR ramoth.cf.ac.uk

I would hope that cache digests are associated with the IP address of
the host they came from, or at least its unique canonical name ? The squid
2.1 cache has a unique_hostname of ramoth.cf.ac.uk, but of course the
squid 1.x doesn't have that parameter.

Andrew

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