excessive packet loss, or, spanning tree for dummies?

[AccuMegalith]

I inherited administration of a blade based production system whose very basic configuration is: GbE2 switches -> 2848 switches -> 2650 routing switch -> firewall applicance. The blade switches and 2848s are cross-connected to one another, and each blade switch connects to both 2848s. Everything has been working fine for 2+ years now, and we hadn't added any blade enclosures, so there was no need to alter the STP configuration.

We've now added a c class enclosure with two GbE2c switches, and I cross-connected them the same way as the GbE2s. I copied the STP settings as appropriate. While I have connectivity, I get upwards of 10% packet loss on the c-class blades, where I get none with the p class. I've disabled ports, fiddled with settings, to no avail. Connectivity is so bad that I can only access the new blades via ILO.

The cabling isn't that complex, and the IP configuration is simple, just one subnet. STP is the only mystery to me.

The HP documentation is fine for telling me how to configure these settings, but that assumes I know what the hell I'm doing. So, having said that, is there a good reference for the ins-and-outs of STP? Preferrably with examples for HP equipment?

[Mohieddin Kharnoub]

Hi

Very detailed and well explained configuration example:
http://cdn.procurve.com/training/Manuals/ProCurve-and-Cisco-STP-Interoperability.pdf

Good Luck !!!