Re: Device mapper multipathing

From: Zhu,Chao <zhuchao_at_gmail.com>
Date: Wed, 12 Jan 2011 09:28:37 +0800
Message-ID: <AANLkTin441vtDH2CQPX1qxXotzRcc715q=01rp_oYfLm_at_mail.gmail.com>

Thanks LS/Rui;
I asked our storage guys to take a look at your sample config and do more test;
We used IBM xiv ARRAY for the test in QA EnV and the configuration was recommended by IBM;
Below is our configuration; Any recommendation? In production we will be using HDS AMS2000 or USPV servers; But we are not at that stage yet (yes, weird production/qa different SAN during POC);

devices {

    device {

        rr_min_io 15

        path_checker tur

        product "2810XIV"

        no_path_retry fail

        vendor "IBM"

        polling_interval 3

        path_grouping_policy multibus

        path_selector "round-robin 0"

        failback 15

    }

    device {

        rr_min_io 15

        path_checker tur

        product "NEXTRA"

        no_path_retry fail

        vendor "XIV"

        polling_interval 3

        path_grouping_policy multibus

        path_selector "round-robin 0"

        failback 15

    }

}

defaults {

    user_friendly_names yes

}

On Tue, Jan 11, 2011 at 5:34 PM, LS Cheng <exriscer_at_gmail.com> wrote:

> Hi
>
> Can you provide the storage maker and model?
>
> Normally Storage vendors provides failover policies such as
>
> # For EVA A/A arrays
> device {
> vendor "HP|COMPAQ"
> product "HSV1[01]1
> \(C\)COMPAQ|HSV[2][01]0|HSV300|HSV4[05]0"
> path_grouping_policy group_by_prio
> getuid_callout "/lib/udev/scsi_id -g -u /dev/%n"
> path_checker tur
> path_selector "round-robin 0"
> prio alua
> rr_weight uniform
> failback immediate
> hardware_handler "0"
> no_path_retry 18
> rr_min_io 100
> }
>
> ## Device attributes for EMC CLARiiON
> device {
> vendor "DGC "
> product "*"
> path_grouping_policy group_by_prio
> getuid_callout "/sbin/scsi_id -g -u -s /block/%n"
> prio_callout "/sbin/mpath_prio_emc /dev/%n"
> path_checker emc_clariion
> path_selector "round-robin 0"
> features "1 queue_if_no_path"
> no_path_retry 300
> hardware_handler "1 emc"
> failback immediate
>
> }
>
>
>
>
> On Tue, Jan 11, 2011 at 6:58 AM, Zhu,Chao <zhuchao_at_gmail.com> wrote:
>
>> not sure if anyone else has updated this thread since it was posted;
>> We ran into issue of delayed path failover (when one path dies/disabled,
>> all IO hang for 30sec-2 min);
>> it wasn't that optimal to have that time IO totally freezed;
>>
>> We were using redhat 5.4 and also tried oracle enterprise kernel;
>>
>> Would be great to hear more inputs;
>>
>> Thx
>>
>>
>>
>> On Wed, Nov 29, 2006 at 7:08 PM, Luca Canali <Luca.Canali_at_cern.ch> wrote:
>>
>>> Hi,
>>>
>>> Is anybody who has used device mapper for Linux willing to share their
>>> experience?
>>>
>>> I have been using Qlogic multipathing so far with the qla2300_conf
>>> module on RHEL3. No problem with it, but I am moving to RHEL4 and the
>>> needed qla2xxx_conf module is missing from their rmps distribution. So
>>> instead I have done a few tests with device mapper multipathing, seems
>>> to work fine so far, but nothing can beat real world experience.
>>>
>>> Thanks,
>>> L.
>>> --
>>> http://www.freelists.org/webpage/oracle-l
>>>
>>>
>>>
>>
>>
>> --
>> Regards
>> Zhu Chao
>>
>>
>>
>

-- 
Regards
Zhu Chao

--
http://www.freelists.org/webpage/oracle-l

Received on Tue Jan 11 2011 - 19:28:37 CST