Using ESXi 5.1, add the portgroup first, then define vlan id for it:
# esxcli network vswitch standard portgroup add -v vSwitch1 -p vlan701
# esxcli network vswitch standard portgroup set -p vlan701 -v 701
# esxcli system settings advanced set -o /NFS/MaxVolumes -i 256# esxcli software vib update --depot=/vmfs/volumes/datastore1/update-from-esxi5.1-5.1_update01.zipFirst, shutdown all your guests. Then put the host into maintenance mode:
~ # esxcli system maintenanceMode get
Disabled
~ # esxcli system maintenanceMode set -e on
~ # esxcli system maintenanceMode get
Enabled
~ # Do reboot:
~ # esxcli system shutdown reboot -r 'rebooting after patch'