Solved

Cisco Catalyst 1900 Switches - dropping ports

Posted on 2002-03-25
9
227 Views
Last Modified: 2010-04-17
I have 3 Cisco switches, one of which is continually dropping ports.

Setup: Fibre links to switches 1 and 3, switch 2 has two redundant links ie 1 to 2 and 2 to 3.

Switch 2 occassionally drops ports. These ports are unable to ping anything.

I'm assuming that there is a configuration problem with the spanning tree algorithm resulting in ports to be foreced into a blocking state. However, I'm not sure how to troubleshoot this?

I have two vlans in use. As an initial step I removed spantree from both vlans, leaving it active only on vlan 1 (ie the management vlan). This seemed to settle the switch down, however port problems have once again become an issue. All cables and the switch itself have been swapped as well.

Does anyone have any suggestions?
0
Comment
Question by:da_h
  • 3
  • 2
  • 2
  • +2
9 Comments
 
LVL 79

Expert Comment

by:lrmoore
ID: 6893989
try setting portfast on for all of your workstation ports, and keep spanning tree on all the uplink ports on all three switches...
0
 
LVL 17

Expert Comment

by:mikecr
ID: 6894543
I agree with Lrmoore. Normally when trunking switches you will use spanning tree on the trunked port. If you use it on all ports you sometimes have a problem.
0
 

Author Comment

by:da_h
ID: 6896021
Thanks for the input guys

Unfortunately, I've already tried the above suggestions. I removed spantree from the two vlans used by machines on the network and left it active only on the management vlan. The management vlan is used by the trunking ports only.

Portfast was already enabled.

Any other suggestions? At this stage I'm thing a call to Cisco may be in order.


0
Connect further...control easier

With the ATEN CE624, you can now enjoy a high-quality visual experience powered by HDBaseT technology and the convenience of a single Cat6 cable to transmit uncompressed video with zero latency and multi-streaming for dual-view applications where remote access is required.

 
LVL 17

Expert Comment

by:mikecr
ID: 6896230
Are you using VTP to trunk your VLANS together?
0
 

Author Comment

by:da_h
ID: 6896490
Yes, mikecr. Any ideas?
0
 
LVL 17

Expert Comment

by:mikecr
ID: 6897067
Without getting a lot of pages going here, check this article and make sure that you have your VTP set up according to Cisco. This will see if you may have overlooked something.
0
 
LVL 1

Expert Comment

by:mmedwid
ID: 6976388
Sounds to me like a duplex issue.  If the ports are set to AUTO detect - the workstations need to be set to auto.  And if the workstations were hard coded to FULL/100 - that would be a particular problem as the switches are only 10BT except for a couple of ports.  The ports would start generating lots of errors in a duplex mismatch and likely shut down.
0
 
LVL 79

Expert Comment

by:lrmoore
ID: 7997466
No comment has been added lately, so it's time to clean up this TA.
I will leave a recommendation in the Cleanup topic area for this question:

I recommend: delete, no resolution validated

If you would like to keep this question open for more expert input, this cleanup effort will get it closer to the top of the list where it will get more visibility for the experts.

if there is any objection or other expert commentary to this recommendation then please post in here within 7 days.
If you feel that your question was not properly addressed, or that none of the comments received were appropriate answers, please post a request in Community support (with a link to this page) to refund your points. http://www.experts-exchange.com/Community_Support/

PLEASE DO NOT ACCEPT THIS COMMENT AS AN ANSWER!

thanks,
lrmoore
EE Cleanup Volunteer
---------------------
0
 

Accepted Solution

by:
SpideyMod earned 0 total points
ID: 8054157
PAQ'd

SpideyMod
Community Support Moderator @Experts Exchange
0

Featured Post

Free Tool: Path Explorer

An intuitive utility to help find the CSS path to UI elements on a webpage. These paths are used frequently in a variety of front-end development and QA automation tasks.

One of a set of tools we're offering as a way of saying thank you for being a part of the community.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Title # Comments Views Activity
Cisco router recommendation for a 1 gig internet connection 11 73
How do I modify Ubigate for new ISP? 2 102
VirtualBOX on GNS3 11 132
unable to set full duplex 100 on WAN interface 11 61
We've been using the Cisco/Linksys RV042 for years as: - an internet Gateway - a site-to-site VPN device - a leased line site-to-site subnet-to-subnet interface (And, here I'm assuming that any RV0xx behaves the same way as an RV042.  So that's …
There are two basic ways to configure a static route for Cisco IOS devices. I've written this article to highlight a case study comparing the configuration of a static route using the next-hop IP and the configuration of a static route using an outg…
After creating this article (http://www.experts-exchange.com/articles/23699/Setup-Mikrotik-routers-with-OSPF.html), I decided to make a video (no audio) to show you how to configure the routers and run some trace routes and pings between the 7 sites…
After creating this article (http://www.experts-exchange.com/articles/23699/Setup-Mikrotik-routers-with-OSPF.html), I decided to make a video (no audio) to show you how to configure the routers and run some trace routes and pings between the 7 sites…

809 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question