Hello, I know this has been discussed a gazillion times, but I haven't seen relation in any of the threads that I read to this case.
One of our clients is having the situation where is receiving AAL5 CRC errors in it's ATM interface. I've read some posts and some Cisco documentation and it does not seem to be HW problem because it's happening on almost every device terminating the VC's, also it's not a cosmetic problem because the client is indeed having VC's flapping connections so it looses connectivity every now and then. I cannot have all configurations due to access restrictions but I will post some configs present in one of the devices. PLEASE do help me.
ATM4/0 is up, line protocol is up
Hardware is ENHANCED ATM PA
Description: ATM P6-10-1
MTU 4470 bytes, sub MTU 4470, BW 149760 Kbit, DLY 80 usec,
reliability 213/255, txload 1/255, rxload 1/255
Encapsulation ATM, loopback not set
4095 maximum active VCs, 11 current VCCs
VC idle disconnect time: 300 seconds
0 carrier transitions
Last input 00:00:00, output 00:00:00, output hang never
Last clearing of "show interface" counters 3d18h
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: Per VC Queueing
30 second input rate 0 bits/sec, 1 packets/sec
30 second output rate 9000 bits/sec, 4 packets/sec
544367 packets input, 83978083 bytes, 0 no buffer
Received 0 broadcasts, 0 runts, 280 giants, 0 throttles
one VC looks like much more affected then others and this would point to the remote side of that VC.
An AAL5 PDU can be made of several ATM cells so be prepared to see some numbers not aligned this is ATM specific.
I guess this ATM Sonet or SDH is used for backup purposes as the traffic load is low.
if only some VCs show errors you should investigate them, and it may be wise to open a ticket with WAN provider and to perform loopback tests on the remote end to see what happens. You also have ATM OAM disabled that does not allow to monitor the VC status.
It requires time and patience to fix it but it should be possible with the methodology described above, loopback tests are intrusive so they can be performed easily only if remote sites have other links to connect to the HQ otherwise you need a maintanance window.
Hello, the cable has already been checked, this device is from a Service Provider and they opened a ticket to us. There are like 7 more VC's in this but I only posted some because of space but all the rest of the VC's have the same high number of CRC's.
I may recommend the client to configure ATM OAM, so I will be looking to some documentation and see how it's done.
This client is very reserved with everything so I'm working wuth my nails here, I will visit the site and retrieve more info, and I'll keep you updated.
This is actually a pretty cool feature, i didn't even know it existed until I was looking for a solution to advertise a subnet (prefix in BGP talk), only if a certain condition existed. This is exactly what conditional advertisements does
j ai une question j ai achete un routeur cisco 887VA-k9 , je le configuré avec la configuration ci- dessous
si je le lier avec mon pc portable sur l un de ses ports directement ça marche toute est bien ( la connexion internet + m...
Attached policy provides CLI access to the Cisco 4G router over text messaging. Two files are in the attached .tar file:
2. PDF with instructions on how to load and use the .tcl file.