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Posts tagged ES460
Nortel ES 460/470 Software 3.7.3 Pulled
0May 23, 2009
Nortel has pulled software release 3.7.3 for their Ethernet Switch 460/470s from their website due to a potential memory leak. I’ve included a few details of the bulletin below;
Background:
A memory leak condition that in some cases has been shown to impact the functionality of the switch has been identified in software release 3.7.3 for the Ethernet Switch 470. This memory leak condition can result in a loss of CLI access and may result in degradation of network operation. This issue has been observed at 2 customer sites and as a result Nortel
has taken the proactive measure to remove the image from the Nortel support portal. The issue is tracked under CRQ02014086Analysis:
The issue is due to memory leak. Nortel is currently investigating the issue, but no root cause has yet been determined. Investigations are on going and a replacement code will be posted as soon as a resolution is available. The symptom of the issue may include the following: Unable to access CLI from the Menu Interface or very slow CLI response. Additionally the switch may exhibit connectivity problems from Device Manager (JDM). As the condition progresses the switch may become unmanageable which could result in stack instability. This stack instability could then lead to reduced functionality and disruption to network traffic. To recover the switch from the memory leak condition a reboot needs to be perfomed. To determine if your switch is impacted, if you monitor the memory usage of the switch you will notice that the available free memory continues to decrease. Memory usage can be monitored from the CLI using the ‘mem-show’ command. On affected networks the free-blocks displayed by the ‘show-mem’ command will continue to decrease the longer the switch
is up.ES470#mem-show
status bytes blocks avg block max block
——- ——— ——– ———- ———-
current
free 4786688 147 32562 4743452 <<< number will keep decreasing
alloc 3086928 7348 420 -
cumulative
alloc 9979152 30147 331 -You may also observce the following repeated messages on the local console (serial port) as additional indicators of the issue:
0x1e65734 (tLLDP): memPartAlloc: block too big – 1522 in partition 0x177e510.
0x1e65734 (tLLDP): memPartAlloc: block too big – 1522 in partition 0x177e510.
0x1e65734 (tLLDP): memPartAlloc: block too big – 1522 in partition 0x177e510.
You can find the entire bulletin here.
Cheers!
Reload command on Nortel Switches
10January 18, 2009
In today’s demanding business environments a lot of changes need to be made remotely and sometimes even the best laid plans go south. Thankfully Nortel offers the “reload” command in their Ethernet Switch and Ethernet Routing Switch series. I don’t believe the command is available for the 1600 or 8600 series. For those folks that are familiar with Cisco routers this command is identical although the syntax is different. If your making changes that could hang the switch or otherwise leave it improperly configured the reload command will automatically restart the switch after a specified interval has passed. If your configuration changes are successful you can cancel the reload command. If you somehow get disconnected from the switch you only need to wait until the switch reloads the original configuration.
ERS5520-PWR#reload ? cancel Cancel a previous scheduled reload force Do not ask for confirmation minutes-to-wait Minutes to wait before reboot <cr>
Cheers!
Ethernet Switch 470 Stack Troubleshooting
14July 22, 2008
I’ve pulled more than a few hairs from my head troubleshooting stack (cascade) link issues when stacking multiple Nortel Ethernet Switch 460 or Ethernet Switch 470 switches together. I thought I would try to throw together a quick process for testing the cascade module and cable. I hope to make a follow-up post covering the Ethernet Routing Switch 5500 series at a later time.
Let me describe a typical scenario and then offer some ways of isolating the potential problem. You have a stack of four ES470s we’ll refer to as Unit 1, Unit 2, Unit 3 and Unit 4. 
We can use the picture to the left to visualize what a stack of four Ethernet Switch 470s might look like. While all the Up/Down stack lights should be green let’s just say that Unit 3 Down and Unit 4 Up is amber.
Let me just warn you that I have yet to figure how to truly identify a bad cascade module (the module that is built into the switch) from a bad cable without using either a cascade module that is know to be good and/or cascade cable that is know to be good in a process of elimination.
How you can determine if you have a bad cascade cable or cascade module?
It’s really pretty easy although it will require you to take the switch down and use the diagnostic boot code. You’ll need to cable up to the serial interface of the switch in order to run the test. When you’re ready go ahead and cold boot the switch. When you see the following, “470-24T Diagnostics 3.6.0.7″ (or something similar since you may not have a 24T but a 48T) you’ll need to interrupt the boot sequence by hitting Ctrl-C (go ahead and hit it repeatedly). You should see something similar to the following;
470-24T Diagnostics 3.6.0.7 Testing main memory - PASSED >> Break Recognized - Wait.. >> Break Recognized - Wait.. Press 'a' to run Agent code Press 'c' to run Cascade external loopback test Press 'd' to Download agent code Press 'e' to display Errors Press 'i' to Initialize config/log flash Press 'p' to run POST tests Press 'r' to Receive cascade test packets Press 's' to Send cascade test packets..
Once your at this point you’ll need to take a single cascade cable and loop it between the Up and Down port of the switch your working on. This will put a physical loop between the two interfaces so we can run and external loopback test across the cascade links. When you’re ready go ahead and select “c” from the diagnostics menu.
Test 501 Stack External Loopback - FAILED NSX SXLB STAK: Stack Upstream Clock Failed. UCR=27 DCR=A7
In my case the Ethernet Switch 470 24 Port switch that I was using failed the loopback test. I then took a cascade cable that I knew to be working and repeated the test. It subsequently failed again which indicates to me that the cascade module is faulty. If you were to select “e” from the diagnostics menu you might seem something similar to the following;
System Resets = 58. Burn-In Loops = 0. Burn-In Errors = 0. Auto-Burn-In = DISABLED Diag Baud = 9600. Error Log: Bad Port Mask = 80000000 Loop Test Error Description: 50 501 STAK: Stack Secondary Rx (1) Timed Out 50 501 STAK: Stack Upstream Clock Failed. Is Cascade Cable Missing? 50 501 STAK: Stack Secondary Rx (1) Timed Out 50 501 STAK: Stack Secondary Rx (1) Timed Out 50 501 STAK: Force Stack RNGO Low Failed Test=0 GCReg=60 50 501 STAK: Force Stack RNGO Low Failed Test=0 GCReg=60 56 501 STAK: Stack Upstream Clock Failed. UCR=27 DCR=A7 56 501 STAK: Stack Upstream Clock Failed. UCR=27 DCR=A7 58 501 STAK: Stack Upstream Clock Failed. UCR=27 DCR=A7
One very important note! You can only stack switches that are running the same version of software (boot code and agent code). I believe the “Base” light will blink amber if you try to stack two switches together that are not running the same software.
You can also confirm a cascade/stacking issue remotely using Nortel’s Device Manager. Here’s a screenshot of two Ethernet Switch 470s stack together. You can see the yellow LEDs on Unit 1 Up and Unit 2 Down.
Device Manager
I will let you know that we’ve had our own share of cascade modules go bad over the past five years. While the cascade modules appear to be “replaceable” they really not designed to be field serviceable. If a switch fails the cascade loopback test it’s really only good for stand alone operation.
Cheers!
