Re: [squid-users] Squid losing connectivity for 30 seconds

>>>>
>>>>>>>>>> Hi,
>>>>>>>>>>
>>>>>>>>>> I am currently facing a problem that I wasn't able to find a
>>>>>>>>>> solution for in the mailing list or on the internet,
>>>>>>>>>> My squid is dying for 30 seconds every one hour at the same
>>>>>>>>>> exact time, squid process will still be running,
>>>>>>>>>> I lose my wccp connectivity, the cache peers detect the squid
>>>>>>>>>> as a dead sibling, and the squid cannot server any requests
>>>>>>>>>> The network connectivity of the sever is not affected (a ping
>>>>>>>>>> to the squid's ip doesn't timeout)
>>>>>
>>>> Hi,
>>>>
>>>> here is the strace result
>>>> -----------------------------------------------------------------------------------------------------
>>>>
>> <snip looks perfectly normal traffic, file opening and closing data
>> reading, DNS lookups and other network read/writes>
>>>> read(165, "!", 256) = 1
>> <snip bunch of other normal traffic>
>>
>>>> read(165, "!", 256) = 1
>>>> ----------------------------------------------------------------------------------------------------------------------------------------------------
>>>>
>>>> Squid is freezing at this point
>>
>> The 1-byte read on FD #165 seems odd. Particularly suspicious being
>> just before a pause and only having a constant 256 byte buffer space
>> available. No ideas what it is yet though.
>>
>>
>>
>>> wccp2_router x.x.x.x
>>> wccp2_forwarding_method l2
>>> wccp2_return_method l2
>>> wccp2_service dynamic x
>>> wccp2_service_info x protocol=tcp flags=src_ip_hash priority=240
>>> ports=80
>>> wccp2_service dynamic x
>>> wccp2_service_info x protocol=tcp flags=dst_ip_hash,ports_source
>>> priority=240 ports=80
>>> wccp2_assignment_method mask
>>>
>>>
>>> #icp configuration
>>> maximum_icp_query_timeout 30
>>> cache_peer x.x.x.x sibling 3128 3130 proxy-only no-tproxy
>>> cache_peer x.x.x.x sibling 3128 3130 proxy-only no-tproxy
>>> cache_peer x.x.x.x sibling 3128 3130 proxy-only no-tproxy
>>> log_icp_queries off
>>> miss_access allow squidFarm
>>> miss_access deny all
>>
>> So if I understand this right. You have a layer of proxies defined as
>> "squidFarm" which client traffic MUST pass through *first* before
>> they are allowed to fetch MISS requests from this proxy. Yet you are
>> receiving WCCP traffic directly at this proxy with both NAT and TPROXY?
>>
>> This miss_access policy seems decidedly odd. Perhapse you can
>> enlighten me?
> Hi,
>
> Let me explain what I am trying to do,(I was hoping that this is the
> right setup) the squids are siblings so my clients pass through one
> squid only (this squid uses icp to check if the object is in my
> network, if not the squid fetches the object from the internet)
>
> if
> miss if miss
> clients-------->WCCP-------->squid------------->ICP----------->Internet-------->WCCP------->squid-------->clients
>
>
> I have over 400Mbps of bandwidth, but one squid (3.1) cannot withstand
> this kind of bandwidth (number of clients), this is why I have created
> a squidFarm
> I have the following hardware: i7 xeon 8 cpus - 16GB Ram - 2 HDDs
> 450GB & 600GB no RAID
> Software: Debian OS squeeze 6.0.3 with kernel 2.6.32-5-amd64 and
> iptables 1.4.8
> Please note that when I only use one cache_dir (the small one
> cache_dir aufs /cache1/squid 320000 480 256 ) I don't face this problem
> The problem starts when the cache dir size is bigger then 320 GB
> Please advise
>
> Thank you for the advise on the refresh patterns
> Regards
> Elie
>
Hi Amos,

Thank you for your help, the problem was solved when I replaced the
refresh patterns with what you recommended,
I replaced more then 20 lines of refresh patterns with 4 lines,

One more question, do you recommend a specific replacement policy, I
have read that when the size of cache directory is large, you advise to
leave the default replacement policy,
Please advise,

Thank you,
Elie
Received on Mon Dec 05 2011 - 06:15:03 MST