Lenovo Flex System Fabric CN4093, Application Manual

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CN4093 Application Guide for ENOS 8.4
Updating Software on vLAG Switches
When updating the software and boot images for switches configured with vLAG,
first:
 Make sure that the spanning tree root switch is not one of the vLAG switches
 Shut down of ports should done under the port configuration
 Follow the shut down order of the ports
a.
ISL links
b.
vLAG links
c.
vLAG health check (MGT port)
Then follow this procedure to update the software on vLAG switches:
1.
On Switch 2 (the original Secondary switch), shut down all links ISL, vLAG links,
and vLAG HC. This is equivalent to powering off Switch 2.
 All the traffic will failover to Switch 1 (the original Primary switch.).
 After the shutdown of links on Switch 2, there will be N ‐ S traffic loss of around
~0.16 seconds.
2.
Upgrade Switch 2 with the new image. Use FTP, STFP, or TFTP to copy the new
ENOS and boot images onto the switch. For more details, see “Loading New
Software to Your Switch” on page 74 .
 After Switch 2 comes up, vLAG HC will be up and vLAG mismatch will happen
with vLAG ports down (since it is still Secondary).
 The traffic will still be forwarding via Switch 1 (the original Primary switch).
3.
On Switch 1 (the original Primary switch), shut down all links ISL, vLAG links, and
vLAG HC. This is equivalent to powering off Switch 1 (the original Primary switch)
 All the traffic will failover to Switch 2, which will assume the vLAG operation
role of Primary.
 After all the links are up on Switch 2, there will be N ‐ S traffic loss of around ~70
seconds due to spanning trees reconverging.
4.
Upgrade Switch 1 (the original Primary switch with the new ENOS image. Use
FTP, STFP, or TFTP to copy the new ENOS and boot images onto the switch. For
more details, see “Loading New Software to Your Switch” on page 74 .
 After Switch 1 comes up, vLAG HC, ISL, and vLAG links will be up, and Switch
1 will assume the vLAG operation role of Secondary.
 All the traffic will now follow the hash and load balance settings between Switch
1 and Switch 2.
 There will be N ‐ S traffic loss of around ~0.05 seconds.
5.
Change the operational role of the vLAG switches to match the final topology by
reloading Switch 2.
 There will be N ‐ S traffic loss of around ~0.102 seconds.