07-27-2012 07:10 PM - edited 03-07-2019 08:01 AM
Hi team,
We have 2 3945/15.0(1)M7 connected via gig interface to upstream routers (4 routers running MPLS BGP in core, dedicated for IP SLA probes) and we can ping physical interface IP just fine no delay but when ping loopback interface ping response time latency varies any where from 1 ms to 22 ms and we are looking for ways to find out if something in control plane of 3900 is causing this delay, any help is much appreciated.
Topology and config is like this
FRFRPARP301NSR01:
sho ip int brief Interface IP-Address OK? Method Status Protocol GigabitEthernet0/0 unassigned YES NVRAM administratively down down GigabitEthernet0/1 10.251.63.117 YES NVRAM up up GigabitEthernet0/2 10.251.63.9 YES NVRAM up up Loopback0 10.250.230.207 YES manual up up Loopback1 10.250.230.206 YES manual up up Loopback2 10.250.230.205 YES manual up up Loopback3 10.250.230.204 YES manual up up
nterface Loopback0 description Router Integrity Enterprise Template rollout for BOA AUDIT Feb 2005 ip address 10.250.230.207 255.255.255.255 ! interface Loopback1 description Tier 1 poller source ip address 10.250.230.206 255.255.255.255 ! interface Loopback2 description Tier 2 poller source ip address 10.250.230.205 255.255.255.255 ! interface Loopback3 description Reserved ip address 10.250.230.204 255.255.255.255 interface GigabitEthernet0/2 description FRFRPARP301GER01B_GE0/0/1/1 mtu 9000 ip address 10.251.63.9 255.255.255.254 no ip redirects no ip proxy-arp duplex full speed auto GigabitEthernet0/2 is up, line protocol is up Hardware is PQ3_TSEC, address is c464.1326.b982 (bia c464.1326.b982) Description: FRFRPARP301GER01B_GE0/0/1/1 Internet address is 10.251.63.9/31 MTU 9000 bytes, BW 1000000 Kbit/sec, DLY 10 usec, reliability 255/255, txload 1/255, rxload 1/255 Encapsulation ARPA, loopback not set Keepalive set (10 sec) Full-duplex, 1000Mb/s, media type is SX output flow-control is XON, input flow-control is XON ARP type: ARPA, ARP Timeout 04:00:00 Last input 00:00:00, output 00:00:00, output hang never Last clearing of "show interface" counters 04:53:18 Input queue: 1/75/0/0 (size/max/drops/flushes); Total output drops: 0 Queueing strategy: fifo Output queue: 0/40 (size/max) 5 minute input rate 257000 bits/sec, 165 packets/sec 5 minute output rate 255000 bits/sec, 163 packets/sec 3170656 packets input, 604643921 bytes, 0 no buffer Received 448 broadcasts, 0 runts, 0 giants, 0 throttles 0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored 0 watchdog, 448 multicast, 0 pause input 0 input packets with dribble condition detected 3173300 packets output, 605343966 bytes, 0 underruns 0 output errors, 0 collisions, 0 interface resets 0 unknown protocol drops 0 babbles, 0 late collision, 0 deferred 0 lost carrier, 0 no carrier, 0 pause output 0 output buffer failures, 0 output buffers swapped out
FRFRPARP301NSR01#ping 10.250.230.223 Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 10.250.230.223, timeout is 2 seconds: !!!!! Success rate is 100 percent (5/5), round-trip min/avg/max = 1/2/4 ms FRFRPARP301NSR01#ping 10.250.230.222 Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 10.250.230.222, timeout is 2 seconds: !!!!! Success rate is 100 percent (5/5), round-trip min/avg/max = 20/22/24 ms FRFRPARP301NSR01#ping 10.250.230.223 Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 10.250.230.223, timeout is 2 seconds: !!!!! Success rate is 100 percent (5/5), round-trip min/avg/max = 1/1/4 ms FRFRPARP301NSR01#ping 10.250.230.221 Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 10.250.230.221, timeout is 2 seconds: !!!!! Success rate is 100 percent (5/5), round-trip min/avg/max = 12/12/12 ms FRFRPARP301NSR01#ping 10.250.230.220 Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 10.250.230.220, timeout is 2 seconds: !!!!! Success rate is 100 percent (5/5), round-trip min/avg/max = 12/12/12 ms FRFRPARP301NSR01# 2nd NSR rtr: FRFRPART301NSR01#sho ip int brief Interface IP-Address OK? Method Status Protocol GigabitEthernet0/0 unassigned YES manual administratively down down GigabitEthernet0/1 10.251.63.245 YES NVRAM up up GigabitEthernet0/2 10.251.63.137 YES manual up up Loopback0 10.250.230.223 YES manual up up Loopback1 10.250.230.222 YES manual up up Loopback2 10.250.230.221 YES manual up up Loopback3 10.250.230.220 YES manual up up (I'm pinging the 1st NSR's loopbacks way above) FRFRPART301NSR01#ping 10.250.230.207 Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 10.250.230.207, timeout is 2 seconds: !!!!! Success rate is 100 percent (5/5), round-trip min/avg/max = 20/22/24 ms FRFRPART301NSR01#ping 10.250.230.206 Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 10.250.230.206, timeout is 2 seconds: !!!!! Success rate is 100 percent (5/5), round-trip min/avg/max = 1/2/4 ms FRFRPART301NSR01#ping 10.250.230.205 Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 10.250.230.205, timeout is 2 seconds: !!!!! Success rate is 100 percent (5/5), round-trip min/avg/max = 12/12/12 ms FRFRPART301NSR01#ping 10.250.230.204 Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 10.250.230.204, timeout is 2 seconds: !!!!! Success rate is 100 percent (5/5), round-trip min/avg/max = 12/12/12 ms FRFRPART301NSR1#
- no interface errors
- cpu is less than 5%
- no controller level errors
Please let me know if any information is required from devices.
thanks
Manish
07-31-2012 12:31 AM
Hi Manish,
I guess there should be some rate limiting in the RIB/CP for ICMP packet for loopback. Because when you say ping the loop back and if you enable the debug for icmp packets and routing... This will say src and dest as the same ip which is routed via the RIB.
By
Karthik
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