Re: [Scst-devel] make error with ubuntu 20.04 and mofed

[Bart V. A. <bva...@ac...>]

On 2020-05-05 19:29, Grant Albitz wrote:
> Hi Bart, they have an ofed listed for ubuntu 20.04, it states beta
> but seems to install just fine. If you don’t want to troubleshoot> beta software I can respect that and can wait =)

Hi Grant,

The MOFED source code did not build on my setup but the MOFED binaries
installed fine. The incompatibility with MOFED 5 was easy to fix. A
candidate fix is available on the trunk.

> I did have one other question, and this may be cosmetic, under normal conditions my initiator/target relationship looks like this, you will note iser:
> 
> May 06 02:21:16 SAN.PSC.Net scst[221485]: Loading and configuring SCST *
> May 06 02:21:16 SAN.PSC.Net systemd[1]: Started LSB: SCST - A Generic SCSI Target Subsystem.
> May 06 02:21:18 SAN.PSC.Net iscsi-scstd[221632]: iSER Connect to 10.10.12.1:3260
> May 06 02:21:18 SAN.PSC.Net iscsi-scstd[221632]: iSER Connect to 10.10.12.1:3260
> May 06 02:21:18 SAN.PSC.Net iscsi-scstd[221632]: iSER Connect to 10.10.12.1:3260
> May 06 02:21:18 SAN.PSC.Net iscsi-scstd[221632]: iSER Connect to 10.10.12.1:3260
> May 06 02:21:18 SAN.PSC.Net iscsi-scstd[221632]: iSER Connect to 10.10.11.1:3260
> May 06 02:21:18 SAN.PSC.Net iscsi-scstd[221632]: iSER Connect to 10.10.11.1:3260
> May 06 02:21:18 SAN.PSC.Net iscsi-scstd[221632]: iSER Connect to 10.10.11.1:3260
> May 06 02:21:18 SAN.PSC.Net iscsi-scstd[221632]: iSER Connect to 10.10.11.1:3260
> 
> If I reboot an initiator, or reboot scst host, often the connections come up and don’t say iser. Dmesg still mentions RDMA:
> 
> HeaderDigest None, DataDigest None, OFMarker No, IFMarker No, OFMarkInt 2048, IFMarkInt 2048, RDMAExtensions Yes
> 
> But I often see this instead:
> 
> May 06 02:18:43 SAN.PSC.Net iscsi-scstd[4209]: Connect from 10.10.12.2:57155 to 10.10.12.1:3260
> May 06 02:18:43 SAN.PSC.Net iscsi-scstd[4209]: Connect from 10.10.12.3:24036 to 10.10.12.1:3260
> May 06 02:18:43 SAN.PSC.Net iscsi-scstd[4209]: Connect from 10.10.12.5:59449 to 10.10.12.1:3260
> May 06 02:18:43 SAN.PSC.Net iscsi-scstd[4209]: Connect from 10.10.12.4:51968 to 10.10.12.1:3260
> 
> If I do service scst restart, everything comes back up iser again.
> 
> Curious if this is just a cosmetic bug or if somehow I am reverting it iscsi instead of rdma when an initiator disconnects and then reconnects.

This may be a race condition. The SCST iSER driver depends on the SCST
iSCSI driver and hence loads after the SCST iSCSI driver. The iSER
transport protocol is only selected if the iSER driver has been loaded.
Maybe the iSCSI logins happen after the SCST iSCSI driver has been
loaded and before the iSER driver is loaded? Are you using scstadmin to
load /etc/scst.conf? This should not happen when using scstadmin because
scstadmin only applies the "enabled" attributes after it has applied all
other attributes from scst.conf. From the scstadmin source code:

	$changes += applyConfigDevices($CONFIG, $force);
	$changes += applyConfigAssignments($CONFIG, $force);
	$changes += applyConfigAlua($CONFIG, $force);
	$changes += applyConfigDeviceGroups($CONFIG, $force);
	$changes += applyConfigEnableTargets($CONFIG, $force);
	$changes += applyConfigEnableDrivers($CONFIG, $force);

Bart.