[squid-users] squid cache peer issues

[Alex Samad]

Hi

seems like .12 is now available for me. I will apply and retest. is
there anything you would like me to do if I see it again ?

A

On 21 December 2015 at 21:26, Amos Jeffries <squid3 at treenet.co.nz> wrote:
> On 21/12/2015 2:00 p.m., Alex Samad wrote:
>> Hi
>>
>> running on centos 6.7
>>
>> 3.5.12 still not available on centos 6.
>>
>> rpm -qa | grep squid
>> squid-helpers-3.5.11-1.el6.x86_64
>> squid-3.5.11-1.el6.x86_64
>>
>> This is the 2 cache_peer statements I use
>>
>> # on alcdmz1
>> cache_peer gsdmz1.yieldbroker.com sibling 3128 4827 proxy-only htcp
>> no-query standby=10
>> #cache_peer alcdmz1.yieldbroker.com sibling 3128 4827 proxy-only htcp
>> no-query standby=10
>>
>> # on gsdmz1
>> #cache_peer gsdmz1.yieldbroker.com sibling 3128 4827 proxy-only htcp
>> no-query standby=10
>> cache_peer alcdmz1.yieldbroker.com sibling 3128 4827 proxy-only htcp
>> no-query standby=10
>>
>> on alcdmz1 with export http_proxy pointing to alcdmz1
>>
>> wget -d  http://fonts.gstatic.com/s/lato/v11/H2DMvhDLycM56KNuAtbJYA.woff2
>> -O /dev/null
>> Setting --output-document (outputdocument) to /dev/null
>> DEBUG output created by Wget 1.12 on linux-gnu.
>>
>> --2015-12-21 11:58:05--
>> http://fonts.gstatic.com/s/lato/v11/H2DMvhDLycM56KNuAtbJYA.woff2
>> Resolving alcdmz1... 10.32.20.111
>> Caching alcdmz1 => 10.32.20.111
>> Connecting to alcdmz1|10.32.20.111|:3128... connected.
>> Created socket 4.
>> Releasing 0x000000000101d540 (new refcount 1).
>>
>> ---request begin---
>> GET http://fonts.gstatic.com/s/lato/v11/H2DMvhDLycM56KNuAtbJYA.woff2 HTTP/1.0
>> User-Agent: Wget/1.12 (linux-gnu)
>> Accept: */*
>> Host: fonts.gstatic.com
>>
>> ---request end---
>> Proxy request sent, awaiting response...
>> ---response begin---
>> HTTP/1.1 200 OK
>> Content-Type: font/woff2
>> Access-Control-Allow-Origin: *
>> Timing-Allow-Origin: *
>> Date: Mon, 30 Nov 2015 04:06:16 GMT
>> Expires: Tue, 29 Nov 2016 04:06:16 GMT
>> Last-Modified: Mon, 06 Oct 2014 20:40:59 GMT
>> X-Content-Type-Options: nosniff
>> Server: sffe
>> Content-Length: 25604
>> X-XSS-Protection: 1; mode=block
>> Cache-Control: public, max-age=31536000
>> Age: 1803109
>> Warning: 113 alcdmz1 (squid) This cache hit is still fresh and more
>> than 1 day old
>> X-Cache: HIT from alcdmz1
>> X-Cache-Lookup: HIT from alcdmz1:3128
>> Via: 1.1 alcdmz1 (squid)
>> Connection: close
>>
>> ---response end---
>> 200 OK
>> Length: 25604 (25K) [font/woff2]
>> Saving to: `/dev/null'
>>
>> 100%[==============================================================================================>]
>> 25,604      --.-K/s   in 0s
>>
>> Closed fd 4
>> 2015-12-21 11:58:05 (1.01 GB/s) - `/dev/null' saved [25604/25604]
>>
>>
>> on gsdmz1
>>
>>
>> wget -d  http://fonts.gstatic.com/s/lato/v11/H2DMvhDLycM56KNuAtbJYA.woff2
>> -O /dev/null
>> Setting --output-document (outputdocument) to /dev/null
>> DEBUG output created by Wget 1.12 on linux-gnu.
>>
>> --2015-12-21 11:58:59--
>> http://fonts.gstatic.com/s/lato/v11/H2DMvhDLycM56KNuAtbJYA.woff2
>> Resolving gsdmz1... 10.32.20.110
>> Caching gsdmz1 => 10.32.20.110
>> Connecting to gsdmz1|10.32.20.110|:3128... connected.
>> Created socket 4.
>> Releasing 0x00000000010a2930 (new refcount 1).
>>
>> ---request begin---
>> GET http://fonts.gstatic.com/s/lato/v11/H2DMvhDLycM56KNuAtbJYA.woff2 HTTP/1.0
>> User-Agent: Wget/1.12 (linux-gnu)
>> Accept: */*
>> Host: fonts.gstatic.com
>>
>> ---request end---
>> Proxy request sent, awaiting response...
>> ---response begin---
>> HTTP/1.1 504 Gateway Timeout
>> Server: squid
>> Mime-Version: 1.0
>> Date: Mon, 21 Dec 2015 00:58:59 GMT
>> Content-Type: text/html;charset=utf-8
>> Content-Length: 3964
>> X-Squid-Error: ERR_ONLY_IF_CACHED_MISS 0
>> Vary: Accept-Language
>> Content-Language: en
>> Age: 1450659540
>> Warning: 113 alcdmz1 (squid) This cache hit is still fresh and more
>> than 1 day old
>> Warning: 110 squid "Response is stale"
>> Warning: 111 squid "Revalidation failed"
>> X-Cache: HIT from alcdmz1
>> X-Cache-Lookup: HIT from alcdmz1:3128
>> X-Cache: MISS from gsdmz1
>> X-Cache-Lookup: MISS from gsdmz1:3128
>> Via: 1.1 alcdmz1 (squid), 1.1 gsdmz1 (squid)
>> Connection: close
>>
>> ---response end---
>> 504 Gateway Timeout
>> Closed fd 4
>> 2015-12-21 11:58:59 ERROR 504: Gateway Timeout.
>>
>>
>> so why does it work from alc and not from gs ???
>
> The alc fetch is going:
>   client->alc->Internet/parent
>
> The gs fetch is going:
>   client->gs->alc->Internet/parent
>
> This is shown in the Via headers.
>
>
> The alc sibling has a response cached which matches. But that required a
> revalidation. (The 113 and 110 Warning headers)
>
> The revalidation failed for some reason (the only-if-cached ?). So it
> output a 504 and sent that back to gs. (The 111 Warning header)
>
> There are several problems here:
> 1) why the revalidation is failing, and
> 2) why the gs peer is not re-trying the fetch via another server (parent
> or DIRECT) after the 504 happens.
> 3) The Age header says ~46yrs ago for the 504 being created,
> suspiciously close to 1 Jan 1970 / unix epoch 0-second.
>
>
> It seems to me you have managed to reproduce
> <http://bugs.squid-cache.org/show_bug.cgi?id=4223>
>
> Amos
>
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