Details
Service console IP address is set to DHCP
vmkernel default route is set to 0.0.0.0 after reboot of ESX server
Failed to establish connection to iscsi targets, vmkernel logs the following errors
iSCSI: bus 0 target 0 trying to establish session 0x6943af8 to portal 0, address xx.xx.xx.xx port
iSCSI: session 0x6943af8 to iqn.YYY-MM.com.array:sn.50412358 failed to connect, rc -5, I/O error
iSCSI: session 0x6943af8 connect failed at xxxx
iSCSI: session 0x6943af8 to iqn.YYY-MM.com.array:sn.50412358 failed to connect, rc -5, I/O error
iSCSI: session 0x6943af8 connect failed at xxxx
Solution
The service console IP Address is setup for DHCP, which is supported for ESX .3.0.X
i.e.