We were looking to upgrade firmware on some Equallogic SANs and therefore the timeout settings when a controller restarts. The hosts connected to this are all ESXi 5.1
From VMware documentation:
Extend the iSCSI login timeout on the ESXi host to 15 – 30 seconds
Source: VMware Equallogic
From Dell documentation:
VMware patch ESXi500-201112001 enables editing of the iSCSI option: Login Timeout value on the ESXi 5.0 host. You can read more about the patch and download it from VMware knowledge base article KB2007680. Dell recommends that customers apply this patch and increase this value to 60 seconds. Doing so ensures that there is sufficient time for all iSCSI logins to occur, regardless of the size of the environment.
Source: PDF for iSCSI settings
Note: As we are running ESXi 5.1 our LoginTimeout setting value was already 15 seconds but it is always best to follow the vendors best practices so the value was set to 60 seconds.
To do this in ESXi 5.0 (with patch) or ESXi 5.1 go to the host. Select Configuration tab -> Software Adapters -> Select iSCSI Software Adapter (vmhbaXX) and click Properties.
This should open up the iSCSI Initiator Properties window. Click Advanced .
When a new window opens scroll down to the LoginTimeout value and change to 60 (mine was 15)
Alternatively you can do this via the command prompt (SSH to the particular host):
esxcli iscsi adapter param set -A <vmhbaXX> -k LoginTimeout -v 60
VMware recommends rebooting the host the to reflect the timeout changes so I put the hosts in maintenance mode while the changes were made and then rebooted.