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I am using two Dell PowerConnect 6248 switches to connect a VMware host vSwitch. A discussion of config of Cisco switches for use with VMware advises to set physical ports connected to vSwitch with bpduguard and portfast. However, Dell switches don't have anything labelled bpduguard in their documentation - there is bpdu-protection which looks similar and bpdufilter which looks same as Cisco bpdufilter:

  • Disable STP on the vSwitch connected ports?
  • Leave STP on and enable portfast on the ports, and forget about bpduguard?
  • Enable bpdu-protection on all ports via global config (it's off by default, and on our switches)
  • Do something else?

Update: I got bpduguard and bpdufiltering confused in the original version of the question. I've updated the question to reflect what options Dell actually provide.

See also: VMware vSwitches and spanning tree

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My reading of that article is that you should enable PortFast and leave bpduguard enabled. The VMware vSwitches pay no attention to the BPDU\STP traffic but it's possible that something could be done in a multihomed guest spanning separate vSwitches that could cause issues that bpduguard might help mitigate. It's far more likely that (re)wiring issues will cause trouble and having portfast+bpduguard in place will prevent a lot of the trouble that can arise when someone gets it into their head that they need to rearrange some cabling.

So enable bpduguard globally, use PortFast for the VMware uplinks (and another port where pure STP might cause problems) and you should be well set up.

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Sorry - I got a bit confused with Dell's different terminology/functions. I can't actually enable/disable bpduguard at all. Dell offer bpdu-protection, which might be the same thing and can only be enabled globally (default is off - so what happens if I switch it on now?) and bpdufilter which looks like something else altogether. – dunxd Dec 23 '10 at 12:57
It is, although they are all related. I've been learning a lot about this myself as your question really intrigued me and I definitely didn't understand the subtleties - this is a very good article about both and how STP, PortFast, bpdu filter and bpduguard interact - The thing that is really important is how they differ when enabled per port vs globally. This is for Cisco kit but I think the assumption should be that the Dells behave the same way. – Helvick Dec 23 '10 at 16:39

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