PVST+ and MST

All right, I'm freaking stumped here. I've got a situation where I need to make PVST+ interoperate with a MST region. The topology is an extremely simple triangle design with a Cisco 3550 (12.2(?)) with uplinks to two HP 2810-48G's and then an uplink between the two HP's completing the triangle. I've got PVST+ running on the Cisco (obvsiously) and MST running on the HP's. One HP is the root of all VLAN's that are needed to be run on the HP's; VLANs 1,24,27. What should be happening is the MST region should look like it's running PVST+ thus injecting it's STP info into each VLAN on the Cisco. When I do a sh spanning-tree on the Cisco I can see the CST root is being picked up correctly for VLAN1. VLAN24 and VLAN27, however, are not being picked up correctly. The 3550 thinks it is the root of those VLANs when in fact it's not. If I check all three switches only the one port on the 3550 is being blocked and it is only being blocked in VLAN1 so I've got a loop in VLAN24 and VLAN27. I've tried everything that I can think of to influence this but nothing is working. I can SPAN a port on the 3550 and see the MRecords for the two MSTI's, but it looks like they are being ignored. Does anyone have any ideas as to what might be the problem?? TIA...

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Comments

unclerico

So here's what's happening:
Cisco will not play nice with other vendor's equipment that runs MST. It will only play nice with its own equipment running MST. When you connect a Cisco to a Cisco with one running PVST+ and the other running MST, it will behave like the documenation states, it will send BPDUs into each PVST instance and block the necessary ports. In my case when I plug in HP to Cisco only the CIST (VLAN1) will converge and block properly. The other VLANs in the other MSTIs will create a loop. Basically Cisco treats MST as traditional STP (CST). Fun stuff.

tomset

Why are you running MST when you're only dealing with a handful of VLANs?

Couldn't you just use the standard RSTP?

unclerico

tomset wrote: »

Why are you running MST when you're only dealing with a handful of VLANs?

Couldn't you just use the standard RSTP?

The scenario I present in this thread is just a mock up of a small switch block found in one of my production environments. This switchblock in my production environment consists of a 4503 and the two HP 2810's (there are many other switch blocks hanging off of the 4503 connected via fiber). The 4503 is running 12.1(?) so it supports only pre-standard MST. HP's support only MST. I have to make PVST+ work with MST because the facility where this is installed is a 24x7x365 operation. I get two times per year to do maintenance on the equipment so in April I will be able to do the required upgrade to the IOS and run MST on the 4503. All other switches in the environment are Cisco so the 4503 will be able to make the MST/PVST+ interaction work fine. We will be gradually replacing the aging Cisco switches in the other switch blocks with HP's. I hope that explains my decision.

EdTheLad

unclerico wrote: »

We will be gradually replacing the aging Cisco switches in the other switch blocks with HP's. I hope that explains my decision.

Blasphemy!!

unclerico

EdTheLad wrote: »

Blasphemy!!

lol...sorry

Netwurk

unclerico wrote: »

We will be gradually replacing the aging Cisco switches in the other switch blocks with HP's. I hope that explains my decision.

Ouch.

I've seen this happen - the server guys get tired of dealing with the network guys, so they use HP switches and get mad when the network keeps going down.

But then they can't blame us because they bypassed us.

Kind of silly if you ask me.

Last time I called HP for support here at work, it took hours to get someone who knew what I was talking about. Then they wanted the serial number for every last device in question to make sure that everything was under warranty or covered by a service contract.

I could go on and on, but I really think switching to HP for your switching needs is just asking for trouble. Trust me, we'd all be better off if HP was still only making workstations and printers.

I miss Compaq.

kpjungle

Netwurk wrote: »

Ouch.

I've seen this happen - the server guys get tired of dealing with the network guys, so they use HP switches and get mad when the network keeps going down.

But then they can't blame us because they bypassed us.

Kind of silly if you ask me.

Last time I called HP for support here at work, it took hours to get someone who knew what I was talking about. Then they wanted the serial number for every last device in question to make sure that everything was under warranty or covered by a service contract.

I could go on and on, but I really think switching to HP for your switching needs is just asking for trouble. Trust me, we'd all be better off if HP was still only making workstations and printers.

I miss Compaq.

Agree, nothing but trouble with HP. From laptops to SAN's. All they care about is getting the sales process over with, and then they leave the customer hanging from there on out.

BADfish10

i like the DL360 380's from hp but that is about it.
There blade centers come with Cisco switch module options for a reason

it is not there strong point IMHO

J

unclerico

Netwurk wrote: »

Ouch.

I've seen this happen - the server guys get tired of dealing with the network guys, so they use HP switches and get mad when the network keeps going down.

But then they can't blame us because they bypassed us.

Kind of silly if you ask me.

Last time I called HP for support here at work, it took hours to get someone who knew what I was talking about. Then they wanted the serial number for every last device in question to make sure that everything was under warranty or covered by a service contract.

I could go on and on, but I really think switching to HP for your switching needs is just asking for trouble. Trust me, we'd all be better off if HP was still only making workstations and printers.

I miss Compaq.

I couldn't disagree more with your sentiments of HP products. They are rock solid switches. As my edge switches age out I am replacing all of them with HP's without even a second thought. There is absolutely nothing that I need done at the access layer that HP cannot handle. Notice that I didn't say I was replacing my core or distribution switches with HP. I will be replacing those with Cisco when the time comes.

In terms of support, EVERY product ever made has had bad support at some point. Even the beloved Cisco has gotten knocked before on their support quality.

In terms of stability, I've not had to contact HP even once about my ProCurves.

The only things from Cisco that I use in my environment are core/distribution switches and routers. WAN Optimization, Video Conferencing, VoIP, and Wireless are all from vendors that specialize in their respective arena's. As a matter of fact Cisco didn't even make our top two or three in any category. Like you, I wish that they would just concentrate on what they do well and that would be switches and routers. They are trying to be everything to everyone and it isn't working. This is of course MY opinion.

Netwurk

Looks like an HP rep just chimed in

Sorry bud, but go ahead and try to troubleshoot a SAN issue sometime

HP does not play nice with Cisco

They can bee-atch all they want about how Cisco stuff is too proprietary and they may have a point there

But if you know your switches don't work with the industry standard, then why fight a silly uphill battle and jump into a market you don't know anything about

Hold on bud, I'll transfer you to their call center rep - with any luck English is his first language

And don't get me wrong - I'm an oldtimer who is very liberal

But I would never try to field a call if the person needing support spoke French or Spanish - I'm not qualified to speak their language fluently and I would not try to pretend I could

HP sux

unclerico

Netwurk wrote: »

Looks like an HP rep just chimed in

Sorry bud, but go ahead and try to troubleshoot a SAN issue sometime

HP does not play nice with Cisco

They can bee-atch all they want about how Cisco stuff is too proprietary and they may have a point there

But if you know your switches don't work with the industry standard, then why fight a silly uphill battle and jump into a market you don't know anything about

Hold on bud, I'll transfer you to their call center rep - with any luck English is his first language

And don't get me wrong - I'm an oldtimer who is very liberal

But I would never try to field a call if the person needing support spoke French or Spanish - I'm not qualified to speak their language fluently and I would not try to pretend I could

HP sux

First of all I'm not a freaking HP rep. I have zero allegiance to any product. I don't like any one company enough to sell their stuff and that includes Cisco. By your logic because you're defending Cisco that must make you a Cisco rep right?? I don't get where the not supporting industry standards argument comes into play. If anyone should be scolded for doing it their way it should be Cisco. HP supports only industry standard protocols as well as CDP (albeit in a scaled down version). Go ahead and try to troubleshoot a Cisco WAAS solution sometime, I hear they are so much fun that they get yanked out of more environments than virtually any other solution on the market. As for speaking English, my only encounters with Cisco support have been with reps that most definitely don't consider English their primary language.

My point in my original post was not to start a brand war. I think everyone knows that Cisco has the market cornered and nobody will ever take it away from them. They have a phenomenal product that is absolutely rock solid. With that said, they are not the only ones with a solid product. Why spend 5k on a 2960 when I can get an HP 2810 with all of the features plus a heck of a lot more throughput for 1/3 of the price?? In these tough economic times it only makes sense to look at solutions that will not only save you money, but will also perform up to expectations.