[Users] way to edit iSCSI storage domain?

[Shu Ming]

Yuriy Demchenko:
> I guess you misunderstood me
> I'm going to try this scheme:
>                |STORAGE|
> FC             /           \
>     |SERV1/tgtd|    |SERV2/tgtd|
> iSCSI       \              /
>          |ethernet switches|
> iSCSI            ||||||||
>        |blades|blades|blades|

I am still confused if SERV1/SERV2 are used as a iSCSI bridge to the 
storage only or used as VDSM host also?  If they are used as VDSM host 
and both of them can have FC channel to the storage, why not create FC 
storage domain for them instead of iSCSI domain?

>
> serv1/serv2 - connectivity isnt a problem, multipathed FC scheme, all 
> good. Same lun accessible for both servers and than exported via tgtd 
> to iSCSI: with different target names ("iqn.2013-03.serv1:store", 
> "iqn.2013-03.serv2:store"), but same vendor_id, product_id, scsi_sn, 
> scsi_id. That way client can login into both targets and see lun as 
> multipathed device.
> And multipath failover scheme (via custom config with 
> path_grouping_policy=failover for corresponding vendor_id/product_id) 
> is on blades-clients - so they use only one target at time (no 
> round-robin or similar stuff), but with ability to switch to another 
> target in case one of serv1/serv2 is down.
>
> However, in my case "serv2" would not be available during oVirt setup 
> (need to setup ovirt and virtual servers to move stuff first), so i 
> cant enter both targets on storage domain initialization - that's why 
> I'm asking if there's any way to edit storage domain details after 
> initialization without destroying it (maybe directly via sql or 
> something).
>
> Yuriy Demchenko
>
> On 04/02/2013 06:26 PM, Shu Ming wrote:
>> I am not sure if the multipathd can recognize the FC path to the 
>> storage when the second server is available and regards it as the 
>> same as the iSCSI path used before. If it is not, I think the device 
>> under /dev/mapper may change when you cut the iSCSI path off and then 
>> enable FC path. That will definitely corrupt the meta data of the 
>> volume group which the storage domain is sitting on and the storage 
>> domain will be corrupted finally. 
>


-- 
---
舒明 Shu Ming
Open Virtualization Engineerning; CSTL, IBM Corp.
Tel: 86-10-82451626  Tieline: 9051626 E-mail:shuming at cn.ibm.com  orshuming at linux.vnet.ibm.com
Address: 3/F Ring Building, ZhongGuanCun Software Park, Haidian District, Beijing 100193, PRC