Finally got a round to trying this, and it seems to be working. Downloaded about 90mb or so of updates off microsoft update, including some large downloads (net framework 2 & 3 service packs) on one machine.
Done the same on the next machine and at first thought "it's not working", then I noticed it was downloading -extremely- fast.... obviously pulling it from the cache
I just added what bjoyce said in his post, done a "squid -k reconfigure", and a squid restart, and away it went.
this is all I added:
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hierarchy_stoplist cgi-bin ?
acl QUERY urlpath_regex cgi-bin \?
no_cache deny QUERY
cache_mem 16 MB
maximum_object_size 1280096 KB
cache_dir ufs /var/spool/squid 3000 16 256
# various windows versions
refresh_pattern http://.*\.windowsupdate\.microsoft\.com/ 0 80% 20160 reload-into-ims
refresh_pattern http://.*\.update\.microsoft\.com/ 0 80% 20160 reload-into-ims
refresh_pattern
http://download\.microsoft\.com/ 0 80% 20160 reload-into-ims
refresh_pattern
http://windowsupdate\.microsoft\.com/ 0 80% 20160 reload-into-ims
refresh_pattern
http://office\.microsoft\.com/ 0 80% 20160 reload-into-ims
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Now I just need to work out how to add avast! anti-virus and java
Cheers,