Troubleshooting Nortel PAg Module issues

Resolving The Problem

Note: Nortel Networks Port Aggregator (PAg) Module for IBM BladeCenter

1. To begin troubleshooting, check the following top issues. If your issue is listed, select the link, otherwise proceed to step 2.
   
   

   	Cannot ping management IP address
   	Cannot connect to the Port Aggregator management interface using telnet
   	Cannot connect to the Port Aggregator management interface using the Web
   	No link on external ports
   	Cannot ping a server blade
   	Cannot transmit and/or receive to/from all addresses on the network
   	Bad response time for large data transfers
   	Amber "!" LED is lit after POST is complete

   
   

2. Download the latest firmware and software code updates for your system:
   
   

   	Download Nortel Networks Port Aggregator firmware
   	Download the latest BladeCenter support software

   
   Note: Whenever you do a firmware update followed by a restart, first check to see if you have 'Preserve new IP configuration on all resets' Enabled. If this function is not enabled, an incorrect IP address could be set in the GbE Switch Module. This would stop all communication between the Management Module and the GbE Switch Module. Always backup the switch configuration before updating the switch's firmware.
   
   
3. Consult the product documentation for the Nortel Networks Port Aggregator:
   
   

   	Port Aggregator Release notes
   	Port Aggregator Installation guide
   	Port Aggregator User's guide
   	Port Aggregator Quick start and Troubleshooting guide
   	Alteon OS 21.0 Application guide
   	Alteon OS 21.0 Command reference
   	Alteon OS 21.0 BBI Quick guide

   
   
4. Nortel switches use the AlteonOS Web GUI for management:
   
   
   
   
   1. Initial setup is performed via MM interface:
      • Configure IP address
      • Enable external ports (disabled by default)
        
        
   2. Management is performed using telnet or http directly to the switch:
      • Configure the switch
      • Gather the switch log
      • Upgrade switch firmware (TFTP or browser)
      • Download and upload switch configuration (TFTP or browser)
        
        
   3. The internal ports to blade servers are fixed at 1000Mbps. The six external ports are set for auto-sensing. The two ports to the BladeCenter MMs operate at 100Mbps. There is a serial console port on the front of the switch that can also be used to manage the switch. The switch supports a range of features for LAN configuration and management including link aggregation, VLANs, STP, and failover.
      
      
5. If these steps have not solved your problem:
   Refer to "Need more help?"
   
   

This condition is commonly caused by incorrect configuration of the management module IP Information, Management IP Address, Network Mask and/or Default Gateway.

1. Verify that the Port Aggregator has successfully booted, by viewing the Monitors > System Status > I/O Modules screen on the management module's Web interface. Verify that the switch status is GREEN.
   • If the status is YELLOW or RED, make note of the POST Status and whether the Post Results are anything other than FF, and the Port Aggregator has been powered on for at least 2 minutes Then refer to "Solving Problems" in the Port Aggregator Module Installation Guide.
   • To recover from the POST Error, it may be useful to Power Cycle the Port Aggregator using the I/O Module Tasks > Admin/Power/Restart screen on the management module Web interface.
   • If the actions listed above do not resolve the POST Error, refer to "Need more help?"
     
     
2. Verify that the management module's External Network Interface (eth0) and Internal Network Interface (eth1) IP configuration are on the same IP subnet as the Port Aggregator, using the Control > Network Interfaces screen on the management module's Web interface. If they are not all on the same subnet, you cannot reach the Port Aggregator.
   
   
3. Verify that the current IP configuration is correct, using the I/O Module Tasks > Configuration > Bay x screen in the management module's Web interface. If the configuration is correct, attempt to re-initialize the IP information by pressing the Save button.
   
   
4. Verify that a ping from the management module to the Port Aggregator is received, using the I/O Module Tasks > Configuration > Bay x > Advanced Management > Send Ping Requests screen in the management module's Web interface. If the ping is successful, then there is probably a routing issue between the Port Aggregator and the workstation. Verify that the Default Gateway is correct on the workstation and Port Aggregator. Also attempt to use the tracert command on your workstation.
   
   
5. After completing the tasks listed above, if you still cannot ping the Port Aggregator, establish a serial connection and perform the following steps using the Port Aggregator CLI. The serial connection is made using a terminal emulator similar to Windows Hyper Terminal (Speed = 9600 bps, Data Bits = 8, Parity = none, Stop Bits = 1).
   • Verify that your IP information initialized by the management module is correct using the command /info/l3/ip. Check that the IP address and Network Mask for IP interface 128 are the values that you expect and that the interface is up.
   • If the interface is down, enter the command /info/link, and validate that the appropriate MGT1 or MGT2 port displays as link up and has a 100 Mbps/full duplex connection. If not, reset the Port Aggregator (/boot/reset) and reset the management module (MM Control >Restart MM). If both links do not come up, refer to "Need more help?" for additional assistance.
   • Verify that the Default Gateway is functioning properly. Use the command /info/l3/ip and check the Default Gateway section of the output. Verify that the gateway is the address that you expect, and correct it on the management module, if necessary. If the gateway is down, verify that the gateway is on the same IP subnet as your management IP address. You also can attempt to ping the gateway address.
   • Use the Port Aggregator command tracert to trace each hop from the Port Aggregator to the device that originally displayed the connection issues. By checking each hop through the network, you can pinpoint the link at which the information is stopping.
     
     

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This condition often is caused either by a bad IP configuration, or by disabled telnet support on the Port Aggregator.

1. Verify that the workstation has a working connection to the Port Aggregator, using the ping command. If not, refer to "Cannot ping management IP address" for additional troubleshooting steps.
   
   
2. Use a serial connection to log into the Port Aggregator CLI. Use the command /cfg/sys/access/cur and verify that telnet is enabled. Also note which port telnet is configured to use- if it is not port 23, then configure your telnet client to use a different port number. If telnet is disabled, enable it (/cfg/sys/access/tnet ena). Apply and save the configuration. The telnet port is controlled using the command /cfg/sys/access/tnport.
   
   Note: To initiate a telnet connection over the management module interface, you must use port 23.
   
   
3. Verify that you can telnet to the management module. If this does not work, verify that there are no filters or firewalls blocking telnet traffic between the Port Aggregator and your workstation.
   
   
4. Attempt to reset the switch, using the CLI (/boot/reset), the BBI (Configure > System > Config/Image Control > REBOOT!), or by power cycling the switch using the management module Web interface.
   
   
5. If the above steps do not resolve the issue, refer to "Need more help?" for additional assistance.
   
   

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This condition is usually caused either by a bad IP configuration or by disabled BBI support on the switch.

1. Verify that the workstation has a working connection with the Port Aggregator, using the ping command. If not, refer to "Cannot ping management IP address" for additional troubleshooting steps.
   
   
2. Use a serial connection to log into the Port Aggregator CLI. Use the command /cfg/sys/access/cur and verify that HTTP (and possibly HTTPS) is enabled. Also note which port HTTP is configured to use-if it is not port 80, configure your browser to use a different port number. If HTTP is disabled, enable it (/cfg/sys/access/http ena). Apply and save the configuration. The HTTP port is controlled using the command /cfg/sys/access/wport.
   
   Note: To initiate a HTTP connection over the management module interface, you must use port 80.
   
   
3. Verify that your browser can access the management module Web interface. If you cannot, verify that there are no filters or firewalls blocking web traffic between the Port Aggregator and your workstation.
   
   
4. Attempt to reset the switch, using the CLI (/boot/reset), the BBI (Configure > System > Config/Image Control > REBOOT!), or by power cycling the switch using the management module Web interface.
   
   
5. If the above steps do not resolve the issue, refer to "Need more help?" for additional assistance.
   
   

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This condition is usually caused by the management module disabling external interfaces, by the Port Aggregator configuration, or by a bad cable.

1. Verify the Port Aggregator configuration. Use the CLI command /info/link and check that the port is not disabled. You can use the BBI Dashboard's Switch Ports screen to check that ports' Operational Status are not offline. If the ports' status is disabled or offline, continue to the following actions:
   
   
2. Verify that the management module has the external ports enabled, by viewing the I/O Module Tasks > Admin/Power/Restart. Under I/O Module Advanced Setup, select the correct I/O module, and verify that the External Ports field is enabled. If not, enable and save the configuration.
   
   
3. Verify that the Port Aggregator does not have the external ports disabled by the Configuration menu or the operations menu. Use the CLI command /cfg/port x/cur (x = ext1 - ext6) and check that the port is enabled. If the port is disabled, enable it with the command /cfg/port x ena. If the port is operationally disabled, enable it using the command /oper/port x/ena.
   
   
4. Replace the Ethernet cable connecting the external port that does not get a link.
   
   
5. If the above steps do not resolve the issue, refer to "Need more help?" for additional assistance.
   
   

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This condition often is caused either by a server blade using a tagged VLAN which causes traffic to be dropped, or by bad IP information on the server blade.

1. View the port statistics for the port in question. From the CLI, use the command /stat/port INTx/brg (where x is the blade that you cannot ping) and observe the dot1PortInDiscards value. From the BBI, view Statistics > Switch Ports and select the Internal Port (INT) for the blade in question and observe the "Bridging (dot1) Statistics" InDiscards value. If the value is incrementing, then the blade probably is configured to transmit 802.1Q tagged frames that the Port Aggregator is discarding. The Port Aggregator can only process frames that are not 802.1Q tagged. Correct the server blade configuration before proceeding.
   
   
2. If the blade (INTx) port does not display any frame discards, observe the discard counters on each of the external ports that are connected. If the discards are incrementing on the external ports, validate that the upstream switch is not configured to transmit 802.1Q frames. For a Cisco Switch, this means that the port cannot be configured as a trunk port.
   
   
3. If the actions listed above do not resolve the issue, validate the link aggregation as described in "Cannot transmit and/or receive to/from all addresses on the network".
   
   

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This condition often is caused by the upstream switch not properly configuring the Static Link Aggregation Group (Ether Channel), or by a bad cable connecting the Port Aggregator to the upstream switch.

1. Verify that all of the external links are connected, and have the same port characteristics. From the CLI, use the command /info/link. From the BBI, view Dashboard > Switch Ports. Each of the ports' speed, duplex and flow control settings must match those on the upstream switch. If these characteristics are not the same for all of the ports on the Port Aggregator and do not match the upstream port to which it is connected, statically configure the settings and do not use auto negotiation.
   
   
2. Check the upstream switch configuration to verify that all ports attached the Port Aggregator are configured as members of the same static link aggregation group (etherChannel).
   
   
3. Perform the steps identified in "Cannot ping a server blade" to determine if external or internal ports are receiving 802.1Q tagged frames.
   
   
4. Check the Port Aggregator port statistics to determine if there are any error frames. From the CLI, use the command /stat/port EXTx/if and check the In/Out Errors. From the BBI, view the Statistics > Port Statistics Total Errors field. Excessive errors may indicate a bad cable connected to an upstream switch. If a large number of errors are observed, connect a new Ethernet cable to the upstream switch.
   
   
5. If the above steps do not resolve the problem, refer to "Need more help?"
   
   

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This condition often is caused by duplex mismatching or bad cables on the uplink ports.

1. Verify that all of the external links are connected, and have the same port characteristics. From the CLI, use the command /info/link. From the BBI, view Dashboard > Switch Ports. Each of the ports' speed, duplex and flow control settings must match those on the upstream switch. If these characteristics are not the same for all of the ports on the Port Aggregator and do not match the upstream port that it is connected to, statically configure the settings and do not use auto negotiation.
   
   
2. Check the Port Aggregator port statistics to determine if there are any error frames. From the CLI, use the command /stat/port EXTx/if and check the In/Out Errors. From the BBI, view the Statistics > Port Statistics Total Errors field. Excessive errors may indicate a bad cable connected to an upstream switch. If a large number of errors are observed, connect a new Ethernet cable to the upstream switch.
   
   
3. If the above steps do not resolve the problem, refer to "Need more help?"
   
   

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The Amber "!" LED indicates that an error condition exists on the Port Aggregator. This is usually a condition that may require immediate attention, such as a Power On Self Test (POST) failure or a Temperature Warning. Perform the following actions to determine the cause of this condition:

1. Use the management module interface POST results to check the System Status. If the POST results are not equal to 0xFF, then a POST error has occurred.
   
   
2. If a Syslog Server is configured, check the server for messages from the Port Aggregator.
   
   
3. If you can ping the Port Aggregator's Management IP Address, check the most recent messages, using the command /info/sys/log.
   
   
4. If the above steps do not resolve the problem, refer to "Need more help?"
   
   

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