[Question]regarding Aging Time for the MAC Table

[kmnii]

I saw the following statement in the document below.

[document]

'https://www.cisco.com/c/en/us/td/docs/switches/datacenter/nexus9000/sw/93x/layer-2-switching/configuration/guide/b-cisco-nexus-9000-nx-os-layer-2-switching-configuration-guide-93x/b-cisco-nexus-9000-nx-os-layer-2-switching-configuration-guide-93x_cha...'

[sentence]

MAC addresses are aged up to twice the configured MAC address table aging timeout.

I think if a frame doesn't enter the switch for a set aging time, it gets deleted from the mac table.

However, looking at the sentences in the above document, it seems that it cannot be deleted up to 2 times.

Can anyone help me understand this phrase?

[Mohsin Alam · Accepted solution]

Usually, the actual MAC address age time is from one to two times the configured value. For example, if you set the MAC address age timer to 60 seconds, learned MAC address entries age out after remaining unused for between 60 and 120 seconds. 

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[kmnii]

Hi mohsiala,

Thanks for your reply.

It's the first time I've seen this concept so I'm a bit confused.

Can you explain a bit more why it is 1 to 2 times? Or, if it is confirmed by documentation, that's fine.

Also, is the general thing you said the same applies to catalyst(IOS-XE) as well as nexus?