Turn the "keepalives" off on the router interface. Look at Bug ID: CSCdm31600 Have a great Christmas! God Bless! Chuck Collins CCNP -------------------------------------------------------------------- I am currently having the same problem right now with a 3640 trunking to a FE card in a 2912MF. If you change to dotq do you see runt packets? The router interface does not collect errors of any kind. TAC just sent me a new 2912. I will let you know if I find anything. Chuck Collins CCNP Your post isn't very clear as to exactly where you are seeing CRC errors - is it just on the switch ports? Or is it on the router as well? I've been having a similar problem with a Catalyst 1900. Its got a port that reported a LOT of CRC and aligmnent errors. Absolutely abysmal file transfer rates (if the files were able to be transferred at all). I swapped cables between the PC and the switch port - no change in the error rates. The NIC was definitely set to 10 Mbps half-duplex operation (as was the switch port) so it wasn't a case of duplex or speed mismatch. I unplugged the PC from the switch port, bypassed the switch plugging the PC directly to a 3COM hub--the file transfer performance of the PC increased dramatically. That was with a bare-bones switch configuration - no trunking, no configuration of VLANs. The switch doesn't show any problems during the POST with any of its hardware... Other ports seem to be fine (but I haven't had time to test every port on the switch). In your case, two options come to mind: 1. See if you've got bad ports that are not being reported by the switch diagnostics. Select ports on your switch that you are not receiving CRC errors on - reconfigure the switch to use those ports as trunk ports (and move your server to a port other than port 23). See if your problem disappears... 2. If you've got a service contract, ask Cisco to send replacement hardware and let them figure out the problem. -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of Rick Thompson Sent: December 18, 2000 10:49 PM To: [EMAIL PROTECTED] Subject: trunking problem Let's see if anyone can figure this one out: Running into an interesting problem with trunking. We have multiple setups running this configuration and running into CRC's on the trunk ports, and slow transfer and corrupted files sent inbetween the vlans. Currently we have had 2 ccie from cisco look at it with no help, and TAC has been working it for 5 days with no luck so far. We have 50 locations with this setup and 6 of them are reporting corrupted files. There is a 3640 router with 2FE and the switch is either a 3524xl or 3548XL, all code, cards, memory and flash are identical. The 3640 is setup as follows: interface FastEthernet0/1 no ip address no cdp enable speed 100 duplex full no ip directed-broadcast interface FastEthernet0/1.1 description Trusted Network encapsulation isl 1 no ip directed-broadcast no ip redirects ip address x.x.x.1 255.255.255.128 interface FastEthernet0/1.2 description Display Network encapsulation isl 2 no ip directed-broadcast no ip redirects ip address x.x.x.129 255.255.255.192 interface FastEthernet0/1.3 description untrusted Network encapsulation isl 3 no ip directed-broadcast no ip redirects ip address x.x.x.193 255.255.255.192 The 3524XL or 3548XL is configured as follows: interface fast ethernet 0/24 description router speed 100 duplex full switchport mode trunk The CRC increment atleast 1 every 7 secs. The more data that gets transfere, the worse it gets. We also see CRC's on port 23 which is the server. I tried switching from isl trunking to dotq and that appeared to slow down the CRC, but that is it. Anybody have any ideas? Rick Thompson CCNA, MCSE __________________________________________________ Do You Yahoo!? Yahoo! Shopping - Thousands of Stores. Millions of Products. http://shopping.yahoo.com/ _________________________________ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] _________________________________ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] _________________________________ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] _________________________________ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]