best practice on handling monthly windows patching cycle

[Scozz]

I currently have a 2  + 1 arbiter replica set. The primary, secondary and arbiter are all in separate data centers. Each month windows patching gets applied automatically to all servers.

My question is what is the best strategy to allow this to happen whilst having a Primary always up. The patching window is split into 2 sessions a morning and an afternoon session so best I can do is separate the Primary and Secondary servers into separate session but the arbiter will have to also fit into either a morning or afternoon sessions. Ideally I would like to accomplish this without any manual intervention.

Thanks

[Kevin Adistambha]

Hi,

I currently have a 2 + 1 arbiter replica set. The primary, secondary and arbiter are all in separate data centers. Each month windows patching gets applied automatically to all servers.
My question is what is the best strategy to allow this to happen whilst having a Primary always up. The patching window is split into 2 sessions a morning and an afternoon session so best I can do is separate the Primary and Secondary servers into separate session but the arbiter will have to also fit into either a morning or afternoon sessions. Ideally I would like to accomplish this without any manual intervention.

There is a great, detailed write-up on how to perform maintenance on a replica set: Your Ultimate Guide to Rolling Upgrades. The general procedure is to perform maintenance on all the Secondaries/Arbiter first, before finally stepping down the Primary and perform maintenance on it.

Another resource that may be of interest is Replica Set Maintenance Tutorials.

Best regards,
Kevin

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