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This is 2620 router, any ideas why it can be so high? It's killing my
router.
Thanks, Tom

19 2439020996 15073273 161821 60.48% 60.63% 60.55% 0 TTY
Background

wrote:

> This is 2620 router, any ideas why it can be so high? It's killing my
> router.
> Thanks, Tom
>
> 19 2439020996 15073273 161821 60.48% 60.63% 60.55% 0 TTY
> Background

Do you have some type of dial backup or something?

--

hsb


"Somehow I imagined this experience would be more rewarding" Calvin
**************************ROT13 MY ADDRESS*************************
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************************************************** ******************

No.
Also this is weird, if I ping the router from the host on the same
network I get response times like this:

5ms
1500ms
5ms
1500ms
5ms
1500ms

weird.

Any ideas, thanks, Tom

>From Cisco docs:


TTY Background

The TTY Background process is a generic process used by all terminal
lines (console, aux, async, and so on).
Normally there should not be any impact on the performance of the
router since this process has a lower priority
compared to the other processes that need to be scheduled by the Cisco
IOS software.

If this process takes high CPU utilization, check whether "logging
synchronous" is configured under "line con 0".
One possible cause could be CSCdy01705 (registered customers only) .


CSCdy01705 Bug Details


Headline High cpu at process TTY Background
Product all Model
Component os Duplicate of
Severity 3 Severity help Status Resolved Status help
First Found-in Version 12.2(10A) All affected versions
First Fixed-in Version 12.3(1.6), 12.3(1.6)T, 12.2(11)T09, 12.3(2.3)B,
12.2(21), 12.2(21.6), 12.2(21.5)S, 12.2(21.7)S,
12.1(21.3)E04, 12.3(7)XI, 12.2(20)S05, 12.1(21.4)EC, 12.2(1S06,
12.2(15)BC02e Version help
Release Notes

A Cisco router may experience high cpu utilization at process TTY
Background when the command "logging synchronous"
is configured under line con 0.

The possible workaround is to remove the command "logging synchronous"
from line con 0, however, this should only
be performed during a scheduled
maintenance window as the router could pause indefinitely just after
removal of the command, possibly requiring a
manual reboot of the router.

wrote:

> No.
> Also this is weird, if I ping the router from the host on the same
> network I get response times like this:
>
> 5ms
> 1500ms
> 5ms
> 1500ms
> 5ms
> 1500ms
>
> weird.
>
> Any ideas, thanks, Tom


One of the redudant links is a dialup....or you have a bug. I guess
you would know if you have dialup links or not. Router generated
packets are process swtiched. You might have a redundant link that's
being hammered.

Also, are you debugging something? "no console logging" (no logging
console??) may be in order.


--

hsb


"Somehow I imagined this experience would be more rewarding" Calvin
**************************ROT13 MY ADDRESS*************************
Due to the volume of email that I receive, I may not not be able to
reply to emails sent to my account. Please post a followup instead.
************************************************** ******************

I was able to get some downtime for the router. Reloaded and
everything is back to normal just like MS Windows.

Thank you, Tom