For iSCSI recommended settings please see Zadara Recommended iSCSI Settings
Fibre Channel although being similar to iSCSI in many ways differs when it comes to applying recommended settings required for using a Zadara VPSA. Unlike iSCSI where properties may be changed with the VMware UI itself, Fibre Channel options are at the HBA driver and/or HBA BIOS levels.
As each card provider may use properties and settings unique to their own HBA card(s), we provide the underyling generic options that you should look to match and configure with recommended settings.
My recommendation is the following for FC:
Property | Recommended Value | Measurement | Comment |
Loop Reset Delay | 20 | seconds | see below note *** |
Enable Lip Reset | No | enabled/disabled | |
Enable Lip Full Login | Yes | enabled/disabled | |
Enable Target Reset | Yes | enabled/disabled | |
Login Retries | 8 | a numeric count | |
Link Down Timeout | 20 | seconds |
Some vendors may set this in ms and this can be a cause for misconfiguration. see below note *** |
Port Down Retry Count | 8 | a numeric count | |
Port Login Timeout | 20 | seconds |
check HBA vendor documentation. see below note *** |
This will allow a maximum of 160 seconds to failover controllers before giving up at 180 seconds which is the threshold that VMware tools will give up, so better to kill the VM before this happens.
The VMware "All Paths Down" scenario will kick in at 180 seconds and begin killing VM’s also complaining a lot.
Further to the above Table, some vendors place retry settings ie: PLOGI in the cards BIOS, so it may be required to check the HBA BIOS and ensure that a suitable retry setting is applied.
*** In some drivers/BIOS where no retry option can be found then it is assumed that VMware defaults to 4 retries. If this is evident then a 40 second (not 20 second) Timeout should be set replacing the 20 seconds in the above table for 40.