With the traditional firmware upgrade process, all stack members had to be reloaded at the same time to avoid a version mismatch and thus there was the need for a maintenance window.
With the Rolling Stack Update (RSU) process, downtime to the environment will be reduced from 7 minutes to few seconds. To determine the availability to the environment you can monitore services or connections with ssh, https, rdp or ping.
Example with two stacked Cisco Catalyst 3750X switches:
1. Verify Health of the Switch Stack
show switch detail Hint: The switch marked with * is the master switch
show switch stack-ring speed
2. Set Boot Time and Enable Persistant Mac
boot time 7
stack-mac persistent timer 0 Hint: This command may take some seconds.
The following warnings will appear:
WARNING: Stack MAC persistency timer value of 0 means that, after a
WARNING: master switchover, the current stack-mac will continue
WARNING: to be used indefinitely.
WARNING: The Network Administrators must make sure that the old
WARNING: stack-mac does not appear elsewhere in this network
WARNING: domain. If it does, user traffic may be blackholed.
3. Find Uplink Ports
Use the following command to identify the uplink ports
do show interfaces status
Gi1/0/23 ISL Uplink connected trunk a-full a-1000 10/100/1000BaseTX
Gi1/0/24 ISL Uplink connected trunk a-full a-1000 10/100/1000BaseTX
Gi2/0/23 ISL Uplink connected trunk a-full a-1000 10/100/1000BaseTX
Gi2/0/24 ISL Uplink connected trunk a-full a-1000 10/100/1000BaseTX
sh etherchannel summary
Group Port-channel Protocol Ports------+-------------+-----------+-----------------------------------------------
1 Po1(SU) LACP Gi1/0/23(P) Gi1/0/24(P) Gi2/0/23(P) Gi2/0/24(P)
4. Define Redundant Uplinks
Hint: In the uplink portchannel only one port per switch should be active. If there are more interfaces shut them down with the shut command.
rsu active (Set this on the master switch)
rsu standby (Set this on all member switches)
5. Execute RSU Procedure
archive download-sw /force-reload /rolling-stack-upgrade /overwrite tftp://22.214.171.124/c3750e-universalk9-tar.150-2.SE8.tar
Hint: This may take about 7 minutes times the number of switches. The /reload option will not reload the switches due of unsaved changes in the running config.
6. Monitor Update Status
show switch stack-upgrade sequence
show switch stack-upgrade status
7. Force Master Switch (Optional)
After the RSU process is completed, the master switch may have changed. If you wish to force a specific switch to become master, you will need to reload the current master switch e.g. 2.
This is done with the command below “reload slot switch-number”. DO NOT, execute the “reload” command, as it will reload the whole stack and cause a 7 minute outage.
reload slot 2
Hint: Use in Configuration mode "switch 1 priority <1-15>" to set the switch priority. Highest value will be master.
- Catalyst 3750-X and 3560-X Switch Software Configuration Guide
- Release Notes
- Bugs (CSCts07947 and CSCtx05704)