Our router every morning has to be rebooted, sometimes we have to do it a couple of times a day. It causes our internet access to go down also, but a reboot brings it right back. It almost appears that it becomes tied up, because I cant even telnet in til reboot, any suggestions?
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Router becomes to busy
- Thread starter skatcb
- Start date
Please, try to monitor cpu and memory utilization (sh proc cpu and show proc mem). If cpu utilization and/or memory utilization become very high post the last outputs obtained before the router hung and, if possible, post also a sh interface output. I know this is a difficult task but those outputs must be as close as possible to the moment the router hung (the worst situation).
Sounds like a memory leak or way tooo many routes or a buffer issue. I've seen all three give the same symptoms. Boot the router, clear the counters, check the various CPU and memory usage as suggested but also check the interface buffers (show buffers) and look for the number of out of memory errors. There should be ZERO. If not, give Cisco TAC a call and have them recommend the correct settings. A second possiblity is you might need to upgrade the IOS to a newer version. I ran into a subtle but fatal NAT issue once that did not appear until I hit a certain number of routes.
MikeS
Find me at
"Take advantage of the enemy's unreadiness, make your way by unexpected routes, and attack unguarded spots."
Sun Tzu
MikeS
Find me at
"Take advantage of the enemy's unreadiness, make your way by unexpected routes, and attack unguarded spots."
Sun Tzu
- Thread starter
- #4
Does this tell anyone anything
Buffer elements:
499 in free list (500 max allowed)
10428113 hits, 0 misses, 0 created
Public buffer pools:
Small buffers, 104 bytes (total 112, permanent 50):
111 in free list (20 min, 150 max allowed)
5008942 hits, 450 misses, 99 trims, 161 created
46 failures (0 no memory)
Middle buffers, 600 bytes (total 25, permanent 25):
23 in free list (10 min, 150 max allowed)
206493 hits, 14 misses, 11 trims, 11 created
5 failures (0 no memory)
Big buffers, 1524 bytes (total 50, permanent 50):
50 in free list (5 min, 150 max allowed)
62083 hits, 0 misses, 0 trims, 0 created
0 failures (0 no memory)
VeryBig buffers, 4520 bytes (total 10, permanent 10):
10 in free list (0 min, 100 max allowed)
0 hits, 0 misses, 0 trims, 0 created
0 failures (0 no memory)
Large buffers, 5024 bytes (total 0, permanent 0):
0 in free list (0 min, 10 max allowed)
0 hits, 0 misses, 0 trims, 0 created
Buffer elements:
499 in free list (500 max allowed)
10428113 hits, 0 misses, 0 created
Public buffer pools:
Small buffers, 104 bytes (total 112, permanent 50):
111 in free list (20 min, 150 max allowed)
5008942 hits, 450 misses, 99 trims, 161 created
46 failures (0 no memory)
Middle buffers, 600 bytes (total 25, permanent 25):
23 in free list (10 min, 150 max allowed)
206493 hits, 14 misses, 11 trims, 11 created
5 failures (0 no memory)
Big buffers, 1524 bytes (total 50, permanent 50):
50 in free list (5 min, 150 max allowed)
62083 hits, 0 misses, 0 trims, 0 created
0 failures (0 no memory)
VeryBig buffers, 4520 bytes (total 10, permanent 10):
10 in free list (0 min, 100 max allowed)
0 hits, 0 misses, 0 trims, 0 created
0 failures (0 no memory)
Large buffers, 5024 bytes (total 0, permanent 0):
0 in free list (0 min, 10 max allowed)
0 hits, 0 misses, 0 trims, 0 created
It seems fine for me:
==========================================================================
SHOW BUFFERS NOTIFICATIONS (if any)
==========================================================================
WARNING: This router has dropped 46 packet(s) (0.00092%) due to a shortage of
'Small buffers'.
WARNING: This router has dropped 5 packet(s) (0.00242%) due to a shortage of
'Middle buffers'.
'Failures' tracks the number of dropped packets due to unsuccessful attempts to
allocate a buffer. This can occur in spite of (or even because of) the router's
attempts to create additional free buffers when their number declines below
minimum.
TRY THIS: Ue the 'show memory' command to check the amount of free memory before
attempting to modify public pool buffers. Increase the minimum number of free
buffers for the affected pool.
The following are initial values that usually work well in buffer tuning:
-permanent: take the number of total buffers in a pool and add about 20%
-minimum: set min to about 20-30% of permanent
-maximum: set to something equal or greater than the sum of permanent and minimum
NOTE: This condition may also occur due to a temporary traffic burst.
CAUTION: Adjusting system buffers requires care, expertise, and follow-up
monitoring. Incorrect adjustments can severely affect hardware (and thus
network) performance.
==========================================================================
SHOW BUFFERS NOTIFICATIONS (if any)
==========================================================================
WARNING: This router has dropped 46 packet(s) (0.00092%) due to a shortage of
'Small buffers'.
WARNING: This router has dropped 5 packet(s) (0.00242%) due to a shortage of
'Middle buffers'.
'Failures' tracks the number of dropped packets due to unsuccessful attempts to
allocate a buffer. This can occur in spite of (or even because of) the router's
attempts to create additional free buffers when their number declines below
minimum.
TRY THIS: Ue the 'show memory' command to check the amount of free memory before
attempting to modify public pool buffers. Increase the minimum number of free
buffers for the affected pool.
The following are initial values that usually work well in buffer tuning:
-permanent: take the number of total buffers in a pool and add about 20%
-minimum: set min to about 20-30% of permanent
-maximum: set to something equal or greater than the sum of permanent and minimum
NOTE: This condition may also occur due to a temporary traffic burst.
CAUTION: Adjusting system buffers requires care, expertise, and follow-up
monitoring. Incorrect adjustments can severely affect hardware (and thus
network) performance.
I agree that this sounds like a memory leak issue, one way to track this is to enable console logging and leave PC connected to log any messages. If you start getting Malloc errors you probably have an IOS or memory issue. If you try this post up the error messages, may give an idea of whats going on.
If you are tracking this using the sh mem command the values you are interested are those under Largest(b)and under free.
If you are tracking this using the sh mem command the values you are interested are those under Largest(b)and under free.
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