You don't need to create 2 igroups for two HBA's. Create an igroup and add two HBA wwpn's to that igroup and map lun to that igroup.
Please create alias for host wwpns on storage side. it is the easy way for identification.
fcp wwpn-alias set Host1_HBA1 <wwpn_HBA1>
fcp wwpn-alias set Host1_HBA2 <wwpn_HBA2>
Create igroup and add fcp-alias of two HBA's to the igroup
igroup create -f -t linux host1_igrp
igroup add host1_igrp1 Host1_HBA1
igroup add host1_igrp1 Host1_HBA2
lun map /vol/vol1/lun1 igroup_host1_igrp
This is the best procedure to follow.