best timeout value for iSCSI access on ESXi 7.0.3c

[Elmo]

Hi all,

I hope you are doing well! 

I want to ask what the best timeout value for iSCSI block access using Cisco UCS will be for HA/metrocluster systems using FlexPod? 

The ESX host is booted from iSCSI LUN. VSC is not used in this case. 

Is the iSCSI timeout value defined on a software ISCSI initiator level (host side) or with the vNic configuration?

 Attached is a screenshot of the boot time config (overlay iscsi card in UCS).

Are the timeout values set in there  conflicting in any way with the ESX host or those do not have effect on the ESX hypervisor's own iscsi timeouts?

Any insight is welcomed and thank you in advance!  

[pedro_rocha · Accepted solution]

Hi,

Normally a good starting point is 60 seconds (which is default for several OSes).

You should always follow official documentation like this: https://docs.netapp.com/us-en/ontap-tools-vmware-vsphere/configure/reference_esxi_host_values_set_by_vsc_for_vmware_vsphere.html#esxi-advanced-configu...

And also check for any notes on the IMT - https://imt.netapp.com/matrix for your config (since using UCS, you can be very specific and get good insights for your config).