Unable to setup iSCSI connection using custom port number

Issue

• We are trying to discover iSCSI storage using custom port number 3261 and it was found that iSCSI target discovery succeeds, but the login process fails with following error:

  # iscsiadm -m discovery -t st -p 192.168.1.5:3261
  192.168.1.5:3261,2 iqn.rhv.demo.iscsi:iscsilun
  
  # iscsiadm -m node -T iqn.rhv.demo.iscsi:iscsilun  -p 192.168.1.5:3261 -l
  Logging in to [iface: default, target: iqn.rhv.demo.iscsi:iscsilun, portal: 192.168.1.5,3261]
  iscsiadm: Could not login to [iface: default, target: iqn.rhv.demo.iscsi:iscsilun, portal: 192.168.1.5,3261].
  iscsiadm: initiator reported error (8 - connection timed out)
  iscsiadm: Could not log into all portals
  

• The same target could be accessed without any issues while using default iSCSI port 3260.