CRC Errors On T-1 Link

[ahegler]

I am receiving Input and CRC errors on a remote router serial interface when a user is trying to save an Exel file. I have loacally looped backed both ends with no errors. I have verified switch port settings and tested all cables. The Telco claims it can find no problems with the line. The local router is a 2610 and the remote is a 7507. Encapsulation is HDLC. Should I adjust the MTU size on the serial interfaces? Any other suggestions before I start swapping

equipment?

[donewald]

CRC's are normally physical type issues, which could include your hardware. Ensure the following before swapping something:

1. Line is clean

2. Cable length does not exeed max recommended (50 ft for T1 for example)

3. Ensure all devices configured for common clock (normally your routers will pull this from the line)

4. Ensure CSU/DSU framing type and other config match your carrier and each other.

Hope that helps,

Don

[hculver]

Are you stating that the CRC errors are only on one end of the WAN circuit? If so, the TELCO may have a problem at the biscuit block. I would again have the TELCO test beyond their NIU (network interface unit) to your CSU/DSU. Also, I've experienced an odd problem associated with saving large files and the problem was that I was bridging and routing yet hadn't configured intergrated bridging and routing.

[ahegler]

Yes I am only getting CRC errors on one end and only when an attempt s made to save this particular Execl file. I have looped back my CSU and serial interfaces on both ends with no errors on several bit patterns. I also increased MTU size on serial interfaces but this made no difference. I guess it is back to having the telco test again and maybe replacing some NIC's in a few PC's.

[binujacob]

Try "compress stac " command on the serial interface and try to copy the particular excel file ...

[ahegler]

Thanks the compress stac solved my issue.