topic Re: Chronic ISCSI / storage failover / failback issue in Network and Storage Protocols

Chronic ISCSI / storage failover / failback issue

amf — Wed, 04 Jun 2025 21:32:25 GMT

I am assigned to work on this chronic ISCSI/storage failover/failback issue.

So here is the issue:

Everytime there is storage failover, the host loses the lun connectivity and there is timeout. Servers needs to be either rebooted or the luns needs to be rescanned in order to connect back. Any thoughts/suggesstions/soulutions would be appreciated.

Thanks,

amf

Re: Chronic ISCSI / storage failover / failback issue

SeanHatfield — Tue, 05 Apr 2016 23:56:01 GMT

The SAN host(s) may require remediation.

First validate the config against the IMT, then perform any required updates.

Likely causes:

-Lack of MPIO, or misconfigured MPIO (if cDOT)

-misconfigured CFO (if 7mode)

-misconfigured network switch (spanning-tree/portfast)

-Missing HUK.

-Unsupported SAN host

Re: Chronic ISCSI / storage failover / failback issue

paulstringfellow — Wed, 06 Apr 2016 13:34:13 GMT

Out of interest what OS are the hosts running, if they're esx hosts I would also pursue vmware, this reconnection issue is a general esx problem.

Re: Chronic ISCSI / storage failover / failback issue

SeanHatfield — Thu, 07 Apr 2016 02:46:28 GMT

Thats a good point. For VMware hosts the recommended settings should be applied with the VSC, some of which require a host reboot to take effect. Some guest instances may need timeouts set as well.

Re: Chronic ISCSI / storage failover / failback issue

amf — Thu, 07 Apr 2016 16:32:54 GMT

Physical Servers running Windows 2008 R2