Recently after upgrading our Core Switches (both 6513's) to 12.2(33)SXI8a we have been seeing OutDiscards on some interfaces (on both the core switches) on WS-X6548-GE-TX line cards. Some of these interfaces are configured as access port, some as trunk and some as ether-channel. The CPU on the primary Core is running at 15% and on the secondary at 11%.
We are also seeing ping packet drops only to some devices connected to primary Core Switch. These packet drops (more like burst) is not continous, but can happen at random time of the day.
I understand Outdiscards can be a result of oversubscription. The datasheet of WS-X6548-GE-TX shows that it only has has a backplane fabric for 8Gbps. The line card shares a 1Gb buffer between groups ports (1-8, 9-16, 17-24, 25-32, 33-40, 41-48) and each block of eight ports is 8:1 oversubscribed.
What I don't understand is why was there no discards before the IOS upgrade and why is the ping packet drops happening only to Primary Core?
http://www.cisco.com/en/US/docs/switches/lan/catalyst6500/ios/12.2SX/release/notes/hardware.html#wp4631273
Please help me to troubleshoot and resolve the issue. Thanks in advance.
