C9300 switches stack master election

[adanek]

Hi Meraki folks,

do you know how C9300 switches behaves in stack master election?

In standard Meraki switches manual election is not possible but how with C9300?

Do you have any URL to documentation? Thank You in advance

[aleabrahao]

Running Meraki firmware the same is valid as for MS. Otherwise (running IOS-XE) it is the same process as for other catalyst switches.

[aleabrahao]

https://www.cisco.com/c/en/us/products/collateral/switches/catalyst-9000/nb-06-cat-9k-stack-wp-cte-en.html

[aleabrahao]

the document is for the 3750-x but the same is valid for the C9300 running IOS.

Master Switch Election

The stack behaves as a single switching unit that is managed by a master switch elected from one of the member switches. The master switch automatically creates and updates all the switching and optional routing tables. Any member of the stack can become the master switch. Upon installation, or reboot of the entire stack, an election process occurs among the switches in the stack. There is a hierarchy of selection criteria for the election.

1. User priority - The network manager can select a switch to be master.

2. Hardware and software priority - This will default to the unit with the most extensive feature set. The Cisco Catalyst 3750 IP Services (IPS) image has the highest priority, followed by Cisco Catalyst 3750 switches with IP Base Software Image (IPB).

Catalyst 3750-E and Catalyst 3750-X run the Universal Image. The feature set on the universal image is determined by the purchased license. The "show version" command will list operating license level for each switch member in the stack.

3. Default configuration - If a switch has preexisting configuration information, it will take precedence over switches that have not been configured.

4. Uptime - The switch that has been running the longest is selected.

5. MAC address - Each switch reports its MAC address to all its neighbors for comparison. The switch with the lowest MAC address is selected

https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst3750x_3560x/software/release/12-2_55_se/configuration/guide/3750xscg/swstack.html#35199

[aleabrahao]

https://documentation.meraki.com/MS/Stacking/Switch_Stacks#Understanding_how_the_Active_Stack_Member_is_Elected

Understanding how the Active Stack Member is Elected

• If all stack members are powered up around the same time, the MS with the lowest MAC address will be elected the Active switch.
• If the stack members are not powered up around the same time, the MS with the highest uptime will be elected the Active switch, regardless of its MAC address.
• The Active switch will remain the Active switch until it's either rebooted or an event occurs that forces another Active switch election (such as stack ports being reconnected).

[bberry]

In the non-Meraki managed stack I can set the switch priority so that the same switch is always the master and there is a pecking order for if that switch goes off line. Does the Meraki Managed flavor have that same capability?

Brent

[aleabrahao · Accepted solution]

Unfortunately not 😕

[adanek]

thank you, what not sure

[aleabrahao]

Do you still have questions about the process?

[adanek]

no, it is fine.