Re: [squid-users] Questions Cache-digest

 On Wed, 20 Jul 2011 10:48:16 -0300, igor rocha wrote:
> Helo,
> I have many doubts about the operation and monitoring Cahe-digests.
>
> I do not know how to access the summaries created by the same, as I
> do?!

  http://$visible_hostname/squid-internal-periodic/store_digest

 Its a compacted binary hash, so all you find out by requesting it is
 whether the peer is providing it, and maybe when it was Last-Modified.

>
> I do not know how to ensure that all cache servers are utilising and
> swapping the summary cache_digests between them , is need  a tag
> referencing she?

 You will see HTTP requests for the URL above being made between them.
 From each squid to each of its peers for their individual digest.

>
> The cache-digests is only an information exchange protocol between
> the
> caches that have to be used with a architecture of a squid (mesh,
> hierarquic, multicast)?

 It is a compressed form of the cache index hashes. The format and
 construction is publicly available so there is nothing preventing other
 cache software from providing digests which Squid can fetch. There are
 also several caching softwares based on Squid which contain it.

>
> Looking at my scenario,  you can point my errors.
> RAM
> #cache_mem 16 MB
> cache_mem 128 MB
> maximum_object_size_in_memory 64 KB
> # HD
> #cache_dir aufs /var/spool/squid 512 16 256
> cache_dir aufs /var/spool/squid 512 16 256
> #maximum_object_size 128 MB
> maximum_object_size 16 MB
> minimum_object_size 0 KB
> # Cache Threshold limits
> cache_swap_low 90
> cache_swap_high 100
> #log_icp_queries on
> # Scenario 4. cache_didests
> #cache_peer 192.168.15.200 parent 3128 3130 roun-robin
> cache_peer 192.168.15.201 parent 3128 3130 digest-url= 192.168.15.200
> 192.168.15.202 192.168.15.203

 Only set digest URL if it is an unusual location (ie not the URL I
 mentioned up above).

 Also " 192.168.15.200 192.168.15.201 192.168.15.203" is not a URL.

 I think you need to remove the whole attempt at configuring digest-url
 option from the cache_peer lines. The defaults should work.

> cache_peer 192.168.15.202 parent 3128 3130 digest-url= 192.168.15.200
> 192.168.15.201 192.168.15.203
> cache_peer 192.168.15.203 parent 3128 3130 digest-url= 192.168.15.200
> 192.168.15201 192.168.15.202
>
> #Tags cache-digest
> digest_generation on
> digest_bits_per_entry 5
> digest_rebuild_period 3600
> digest_rewrite_period 3600
> digest_rebuild_chunk_percentage 10
> digest_swapout_chunk_size 4096  bytes
>
 <snip>

 Amos
Received on Thu Jul 21 2011 - 00:25:17 MDT