[sr-dev] git:master:6d87794c: ndb_redis: Added REDIS-Cluster support [BETA]

[Daniel-Constantin Mierla]

Hi Carsten,


On 18.04.17 12:20, Carsten Bock wrote:
> Hi Daniel,
>
> after some further testing, I have to admit, you are right. However,
> I've noticed another issue with ndb_redis, which is associated with
> this issue: The File-Discriptor is also corrupt, when reconnecting to
> ReDIS (e.g. connection was down or similar), as the new connection is
> done in the child process. I have a setup, where I connect to REDIS
> using stunnel and it happens quite frequently, that I have to
> reconnect.
>
> A workaround for this, is to store the information about the
> connection status in the structure as well. Once I had to reconnect
> (which happens from a child process, so corrupt file descriptors), I
> need to reconnect each time I use REDIS. This is not the nicest
> solution, but solves the issue about corrupt file-descriptors. I've
> had this change running for ~5 days now.

I expect you have to reconnect only once from each child when the redis
server connection structure is in private memory.

Maybe I don't understand exactly what do mean by 'reconnect each time'.
I don't have any experience with redis cluster, but with single redis
server each kamailio worker process needed to reconnect just once.

Cheers,
Daniel

>
> Please let me know your thoughts.
>
> Thanks,
> Carsten
>
>
> 2017-04-04 17:02 GMT+02:00 Daniel-Constantin Mierla <miconda at gmail.com>:
>> Hi Carsten,
>>
>>
>> On 04.04.17 14:43, Carsten Bock wrote:
>>> Hi Daniel,
>>>
>>> i've just noticed, that in one line, I tried to free a reply from
>>> shmem instead of pkgmem (fixed).
>> ok, I see.
>>
>>>  I only put the list of
>>> REDIS-Connections into shmem, so other workers can access (and re-use)
>>> the newly added connections to REDIS.
>> Is this safe? If there is a tcp connection behind and the structure
>> references it via the file descriptor, then it is not going to work for
>> connections opened after kamailio forks the child processes.
>>
>> Cheers,
>> Daniel
>>
>>> Note to myself: I should add some locking to the list....
>>>
>>> Thanks,
>>> Carsten
>>>
>>> 2017-04-04 13:11 GMT+02:00 Daniel-Constantin Mierla <miconda at gmail.com>:
>>>> Hello,
>>>>
>>>> I haven't checked the merged version, but if I spotted correctly from
>>>> the patch, it moves the redis response structure in shared memory.
>>>>
>>>> Is is right? If yes, why? Having it in shared memory will create races
>>>> between kamailio processes that store results on same container id --
>>>> one worker can overwrite on data stored by another ine.
>>>>
>>>> Cheers,
>>>> Daniel
>>>>
>>>> On 04.04.17 12:55, Carsten Bock wrote:
>>>>> Module: kamailio
>>>>> Branch: master
>>>>> Commit: 6d87794cac3f6f3bb967d6e0bf6714a4d78f1bd5
>>>>> URL: https://github.com/kamailio/kamailio/commit/6d87794cac3f6f3bb967d6e0bf6714a4d78f1bd5
>>>>>
>>>>> Author: Carsten Bock <carsten at ng-voice.com>
>>>>> Committer: Carsten Bock <carsten at ng-voice.com>
>>>>> Date: 2017-04-04T12:55:26+02:00
>>>>>
>>>>> ndb_redis: Added REDIS-Cluster support [BETA]
>>>>>
>>>>> ---
>>>>>
>>>>> Modified: src/modules/ndb_redis/doc/ndb_redis.xml
>>>>> Modified: src/modules/ndb_redis/doc/ndb_redis_admin.xml
>>>>> Modified: src/modules/ndb_redis/ndb_redis_mod.c
>>>>> Modified: src/modules/ndb_redis/redis_client.c
>>>>> Modified: src/modules/ndb_redis/redis_client.h
>>>>>
>>>>> ---
>>>>>
>>>>> Diff:  https://github.com/kamailio/kamailio/commit/6d87794cac3f6f3bb967d6e0bf6714a4d78f1bd5.diff
>>>>> Patch: https://github.com/kamailio/kamailio/commit/6d87794cac3f6f3bb967d6e0bf6714a4d78f1bd5.patch
>>>>>
>>>>>
>>>>> _______________________________________________
>>>>> sr-dev mailing list
>>>>> sr-dev at lists.sip-router.org
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>>>> --
>>>> Daniel-Constantin Mierla
>>>> www.twitter.com/miconda -- www.linkedin.com/in/miconda
>>>> Kamailio Advanced Training - May 22-24 (USA) - www.asipto.com
>>>> Kamailio World Conference - May 8-10, 2017 - www.kamailioworld.com
>>>>
>>>
>> --
>> Daniel-Constantin Mierla
>> www.twitter.com/miconda -- www.linkedin.com/in/miconda
>> Kamailio Advanced Training - May 22-24 (USA) - www.asipto.com
>> Kamailio World Conference - May 8-10, 2017 - www.kamailioworld.com
>>
>
>

-- 
Daniel-Constantin Mierla
www.twitter.com/miconda -- www.linkedin.com/in/miconda
Kamailio Advanced Training - May 22-24 (USA) - www.asipto.com
Kamailio World Conference - May 8-10, 2017 - www.kamailioworld.com