The dynamic addition and removal of VLANs in SEAs with load sharing is supported by IBM. This means that in principle VLANs can be added or removed at any time. However, it is possible that there may be a brief delay in the forwarding of Ethernet frames.
IBM recommends resetting both SEAs to failover, before adding or removing VLANs (ha_mode=auto):
$ vios chdev ms05-vio1 ent46 ha_mode=auto
$ vios chdev ms05-vio2 ent44 ha_mode=auto
$
Then VLANs can be added or removed, starting with the primary SEA (here the VLAN 16 is added to the trunking adapter ent42 on virtual I/O server ms05-vio1):
$ lpar addvlan ms05-vio1 72 16
$
The VLAN is available immediately.
The same VLANs are then added or removed for the backup SEA (the trunking adapter is ent40 on virtual I/O server ms05-vio2):
$ lpar addvlan ms05-vio2 72 16
$
After all changes have been made to both SEAs, the VLANs of both SEAs should be checked again (“vios lssea -V“):
$ vios lssea -V ms05-vio1 ent46
SEA LNAGG NAME TYPE VSWITCH MODE ACTIVE PRIORITY PVID VLAN_TAG_IDS
ent46 - ent3 real - - - - - -
ent46 - ent45 virtual ETHTEST3 VEB True 1 5 23
ent46 - ent44 virtual ETHTEST3 VEB True 1 4 20,21,22
ent46 - ent43 virtual ETHTEST3 VEB True 1 3 17,18,19
ent46 - ent42 virtual ETHTEST3 VEB True 1 2 14,15,16
ent46 - ent41 virtual ETHTEST3 VEB True 1 1 11,12,13
ent46 - ent39 control ETHCTRL - - - 1 None
$
$ vios lssea -V ms05-vio2 ent44
SEA LNAGG NAME TYPE VSWITCH MODE ACTIVE PRIORITY PVID VLAN_TAG_IDS
ent44 - ent5 real - - - - - -
ent44 - ent43 virtual ETHTEST3 VEB False 2 5 23
ent44 - ent42 virtual ETHTEST3 VEB False 2 4 20,21,22
ent44 - ent41 virtual ETHTEST3 VEB False 2 3 17,18,19
ent44 - ent40 virtual ETHTEST3 VEB False 2 2 14,15,16
ent44 - ent39 virtual ETHTEST3 VEB False 2 1 11,12,13
ent44 - ent38 control ETHCTRL - - - 1 None
$
The added VLAN 16 is displayed correctly for both SEAs.
Finally, the SEAs are configured for load sharing again by setting the ha_mode attribute back to sharing:
$ vios chdev ms05-vio1 ent46 ha_mode=sharing
$ vios chdev ms05-vio2 ent44 ha_mode=sharing
$
A check of the distribution of the VLANs shows that both SEAs are active again (for their VLANs):
$ vios lssea -V ms05-vio1 ent46
SEA LNAGG NAME TYPE VSWITCH MODE ACTIVE PRIORITY PVID VLAN_TAG_IDS
ent46 - ent3 real - - - - - -
ent46 - ent45 virtual ETHTEST3 VEB False 1 5 23
ent46 - ent44 virtual ETHTEST3 VEB False 1 4 20,21,22
ent46 - ent43 virtual ETHTEST3 VEB True 1 3 17,18,19
ent46 - ent42 virtual ETHTEST3 VEB True 1 2 14,15,16
ent46 - ent41 virtual ETHTEST3 VEB True 1 1 11,12,13
ent46 - ent39 control ETHCTRL - - - 1 None
$