[openfabrics-ewg] open-iscsi update for OFED 1.2

[Erez Zilber]

Michael S. Tsirkin wrote:
>> Quoting r. Erez Zilber <erezz at voltaire.com>:
>> Subject: open-iscsi update for OFED 1.2
>>
>> Hi,
>>
>> We would like to add an update for open-iscsi for OFED 1.2.
>>
>> open-iscsi uses iSER as a transport (it also uses TCP and other
>> transports). The interface between open-iscsi and its transports should
>> not be broken. The problem is that while iSER is making progress, it
>> still has to adjust itself to old open-iscsi versions (like open-iscsi
>> in SLES 10) by applying backward patches on iSER. It means that progress
>> and bug fixes that were made are not reflected in OFED.
>>     
>
> I don't get it.
> Other protocols seems to manage fine using updated code for new kernel and
> backports for old kernel.  Why can't iSER made to work with whatever version of
> open-scsi is installed?
>
>   
Unlike protocols such as SRP, iSER cannot exist by itself. The
open-iscsi version in SLES 10 with iSER from OFED 1.1 is not stable
enough because of bugs in open-iscsi. Therefore, even if we backport the
latest version of iSER, open-iscsi+iSER will still be unstable. If we
want people to use iSER, we must supply a stable version of
open-iscsi+iSER.
>> Therefore, we would like to do the following: if the user selects iSER
>> when installing OFED, open-iscsi (userspace & kernel) will be updated if
>> necessary (i.e. if the interface between open-iscsi and iSER from OFED
>> doesn't match). No backward patches will be applied on iSER.
>>
>> Thanks,
>>     
>
> Problem is, people tend to do "install all".
>
>   
We propose the following solution:

    * open-iscsi + iSER will be installed by default.
    * if open-iscsi (userspace code) with version < our open-iscsi
      version is installed, the installation will fail and the user will
      be prompted. The user can decide not to install iSER or uninstall
      his old open-iscsi package. Then, he can rerun the installation.

-- 

____________________________________________________________

Erez Zilber | 972-9-971-7689

Software Engineer, Storage Team

Voltaire – _The Grid Backbone_

__

www.voltaire.com <http://www.voltaire.com/>