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vtp summary adverstisement

hi every body!

Let say we have two switches , sw1 and sw2

sw1 is vtp server, sw2 is vtp client

sw1 has config revision=2,

sw2 has config revision=1,

According to cisco documents, follwing would take place:

1) sw1 send summary adverstisement at multicast address.

2) sw2, receives the summary advetisement , check the domain name if it matches, then check if config revision number is higher than its own.

3) sw2 send the advertisement request.

4) sw1 receives the advertisement request

and send summary advertisement which this time contains the number which indicates the number of subset advertisements to follow this summary advertisement.

5) sw1 sends subset advertisement or advertisements

My questions are:

1) When sw1 send the summary advertisements first time, what the field" number of subset advertisements to follow" in summary advertisement contain? was it zero? if the field was not zero but contains the certain number, then sw1 should not send summary advertisement which contain

the number indicating the number of subset advertisements to follow in response to advertisements request from switch in client mode as switch in client mode knows how many subset advertisements to expect from sw1.

Am i correct?

thanks a lot!


Re: vtp summary adverstisement

By default, Catalyst switches issue summary advertisements in five-minute increments. Summary advertisements inform adjacent Catalysts of the current VTP domain name and the configuration revision number.

When the switch receives a summary advertisement packet, the switch compares the VTP domain name to its own VTP domain name. If the name is different, the switch simply ignores the packet. If the name is the same, the switch then compares the configuration revision to its own revision. If its own configuration revision is higher or equal, the packet is ignored. If it is lower, an advertisement request is sent.

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