Kannan, Is your router running on a multi-homed ISP environment?
Is so, you could have a case of large BGP advertisements from your ISPs causing high router CPU utilization cycles that actually influence the "HSSI interface flapping". I'd suggest that you check the following: 1. Monitor CPU utilization on the routers. They could be exceeding their CPU cycles every time at least one of them receives BGP updates from its upstream router. 2. If the router has an extensive (over 30 lines) of access lists. Trim them down a bit. 3. Check if your ISP is sending FULL or Partical BGP route updates. You may be ok with just partial BGP updates. 4. Analyze the 'show ip bgp neighbors' command output. Check if there are a large number of withdrawn prefixes, also the total size of the BGP prefixes 5. Check the IOS release notes for any existing Bugs. 6. What iBGP protocol are you using? It is often the case that a misconfigured iBGP (EIGRP, OSPF, etc) can cause router "mis-behavior" that gets blamed on BGP. 7. Verify that the HSSI interface is clear of Input errors, use the command 'show int hssi x/y' Hth, Good luck, Angel Leiva - MCSE, CCNA, CCNP-WAN -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of Kannan Sadagopan Sent: Monday, October 22, 2001 5:20 AM To: [EMAIL PROTECTED] Subject: HSSI interface flapping - reg [7:23757] We are running bgp on one of our HSSI interfaces and the interfaces are flapping for a maximum of 4 seconds flapping at least 10 times a day. What could be the reason for the same? Please throw some light on this problem. K. Sadagopan Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=23786&t=23757 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
