Unanswered Question
Oct 20th, 2009
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Hi all,

I am trying to decide which spanning tree mode to run on my DMZ switches.

On the switches I have 12 VLANs. Contained within the VLANs are multiple email servers, web servers, etc.

The switches (2960G 48-Port) are connected together via two crossover cables (ports 45 & 46).

The switches are currently configured to use PVST. I understand the principles of both modes but am somewhat unsure of which mode to deploy.

We deploy RSTP on the LAN switches, there is no communication between the LAN and DMZ switches.

The servers that are patched into the DMZ switches are active-active for redundancy.

Any advice?



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Jon Marshall Tue, 10/20/2009 - 16:43
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If you have the choice of PVST or RSTP i would always go for RSTP simply because you have nothing to lose and you gain on the time it takes STP to reconverge.

If all your switches support it i can't think of a reason not to run RSTP to be honest.


darren-carr Tue, 10/20/2009 - 17:27
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Hi John

Thanks for the prompt reply.

I was leaning towards RSTP after conducting my research, but I wasn't sure if there was any particular reason why whoever deployed these switches would have opted for this configuration given that RSTP is available on the switch?

Silly question (as I don't have similar switches to test this on) by default do these switches IOS 12.2 (25) come with PVST enabled? and this is just an out the box configuration?




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