Re: Packet Loss on Cisco 877

johnlloyd_13 · ‎02-08-2011

hi all,

we have a 877 and a 8 port dumb switch connected behind this router. we have replaced a new router and switch but there's still packet drops on our connection. local loop was tested ok by the telco. strange thing is that when i shutdown the vlan interface, no packet drops towards our ISP. but when interface is up, there's packet drops on the link. router config is plain setup: WAN and LAN ip address and default route to ISP. any ideas how to rectify this issue? thanks!

877#conf t

Enter configuration commands, one per line. End with CNTL/Z.

877(config)#int vl1

877(config-if)#shut

877(config-if)#^Z

877#ping 203.120.X.X rep 1000 >>> ISP PE ROUTER

Type escape sequence to abort.

Sending 1000, 100-byte ICMP Echos to 203.120.X.X, timeout is 2 seconds:

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

!!!!!!!!!!!!!!!!!!!!

Success rate is 100 percent (1000/1000), round-trip min/avg/max = 8/17/96 ms

877#conf t

Enter configuration commands, one per line. End with CNTL/Z.

877(config)#int vl1

877(config-if)#no shut

877(config-if)#^Z

877#ping 203.120.X.X rep 1000

Type escape sequence to abort.

Sending 1000, 100-byte ICMP Echos to 203.120.X.X, timeout is 2 seconds:

.!!!!!!!!.!!!.!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

!!!!!!!!!!!!!!!!!!!!!!!.!!!!!!!!!!!..!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!.!

!!!.!!!.!!!!!!!!!!!!!!!!.!!!!!!!!!!!!.!!!!!.!!!!!!!!.!!!!!!!!!!!!!!!.!

!!!!!!!!!!!!.!!!!!!!!!!!!!!!!.!!.!!!!!!!!!!!!!.!.!!!!!!!!!!!!!!!!!!!!!

!!!!!!!!!!.!!!!!!!!!!!.!!!!!!!!!!!!!!!!!!!!.!!.!!!!!!!!!!!!...!!!!!!.!

!!!!!.!!!!!.!!!!.!!.!!!!!.!!!!!!!!!!!!!!.!!!!!..!!!!!!!!!!!!!!!!!!!!.!

!!!!!!!.!!!!.!!!!!!.!!!!!!!!!!!!!!!!!!!!!!!.!!!!!!!!!.!!!!!!!!.!!!!!!!

!!!!!!..!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

!!.!!!!!!!!.

Success rate is 91 percent (526/572), round-trip min/avg/max = 8/23/88 ms

Latchum Naidu · ‎02-09-2011

Hi,

Can you please post the vlan1 configuration.

And for what purpose you are using vlan1, is it for LAN communication?

Regards,

Naidu.

Amit Singh · ‎02-09-2011

Have you tried an extended ping with the vlan interface up using the source address of the WAN interface of the router? What happens with this scenario? This will give us an idea if the router is using VLAN interface IP as a soruce address when its up and pinging or it is still using the WAN interface and there is something else within the router when the VLAN interface is up.

Do you have any QOS configured on this router? Please attach the router configuration if possible.

Cheers,

-amit singh

Latchum Naidu · ‎02-09-2011

Hi,

Can you please post the vlan1 configuration.

And for what purpose you are using vlan1, is it for LAN communication?

Regards,

Naidu.

johnlloyd_13 · ‎02-10-2011

sorry, my bad. it's just a speed/duplex mismatch on the remote device. pings
100% now