Search squid archive

Re: prevent attempts to go outside for any noncached objects during offline_mode on

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On 10.09.2012 23:48, Oguz Yilmaz wrote:
Hi,

I have read on working of offline_mode in the list. It is an
aggressive caching parameter which prevent refreshing of already
cached object and gives from the cache. However, if the object is not
cached, it try to look for the object thru direct or cache peer. Do
you have any suggestions for implementing a "completely offline" state
with current squid parameters to prevent attempts to get uncached
objects, also

offline_mode is very badly named. It does not mean *offline* at all.

What it does is enable an extra-greedy caching policy to preserve data in cache even if it is very likely to be replaced immediately on next request (normally Squid tries to ignore these to save on disk I/O load).

Since squid-2.6 the particular actions which offline_mode used to be needed for in 2.5 and older have been slowly made into defaults and obsoleted by HTTP/1.1 performance features. The only remaining use for offline_mode is to ensure that *everything* gets added to cache; for example prior to a planned parent web server outage/upgrade so that the reverse-proxy can service the site(s) while *that* server is offline.

For preventing clients getting MISS traffic use miss_access (ie "miss_access deny all" is what you describe above). Squid will still require network access for DNS etc, but the requests matching your miss_access ACLs won't get served any non-cached responses.

Amos



[Index of Archives]     [Linux Audio Users]     [Samba]     [Big List of Linux Books]     [Linux USB]     [Yosemite News]

  Powered by Linux