2900XL; giants on trunk

[m.rainer]

Hallo,

We have a LAN with 4 catalyst 5509 switches in the distribution layer. At the access layer there are about 100 switches. About 50 of that switches are catalyst 2900XL. On most of the 2900XL switches' trunk interfaces we have massive input errors. All of that errors are giants. Many of the switches have exactly the same quantity of input errors after 24 hours. I found out, that most of that errors are on trunk ports where the spanning tree is on blocking state. Maybe there is a relation?!

The 5509 are configured with trunk isl on. (set trunk 1/1 on isl 1-1005

)

Has anybody an idea what is going on here?

Thanks a lot

Max

[Roberto.Rodriguez]

This happened to me several years ago, refer to this link:

http://www.cisco.com/en/US/tech/tk389/tk390/technologies_configuration_example09186a008009441a.shtml

Snippet form the page:

"Currently, Catalyst 2900XL/3500XL switches do not support Dynamic Trunking Protocol (DTP). Thus, it is recommended that you use the nonegotiate option the other side of the trunk link as configured for the Catalyst 4000, 5000, and 6000 switches. This way, the XL switch port will not receive DTP frames that are unfamiliar to it."