Troubleshooting Ethernet Switch Module (ESM) issues

Resolving The Problem

Note: 13N0568 replaces 48P7054 - 4-port Ethernet Switch Module (ESM)

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

   	Basic troubleshooting and log collection guide in a switch crash scenario
   	4-port GBESM requires Blade Flow Control activation
   	Configuring IP address on the ESM interface (BladeCenter T)
   	ESM switch settings changed after updating DLink ESM firmware
   	ESM trunk settings lost when upgraded to new firmware level
   	Intermittent connection loss to BladeCenter Ethernet switch
   	No link on ESM and Cisco when set to manual 1GB/Full Duplex
   	Port PVID settings changed from Tagged to Untagged
   	First ping from ESM through Telnet reports failure
   	ESM firmware graphic shows blank panel when blade server is present but powered off
   	ESM log reports elapsed time, not time of day
   	Ethernet disconnect notice will not appear running Windows 2000
   	The default IP address set by ESM does not match the one assigned by the MM
   	Updating ESM configuration through the MM doesn't save the switch NVRAM

   
   
2. Through the MM, verify all ESMs have a valid TCP/IP address. All ESMs must have a valid TCP/IP address. There is a default address but this will, in all production environments, need to be changed to work with the client’s LAN numbering scheme.
   
   
3. Through the MM, verify that the External ports are enabled. By default, all new ESMs have their external ports disabled for security purposes. These must be enabled before any devices can communicate with Blade Servers.
   
   
4. Through the MM, verify that Management over external ports is enabled (if direct connect management is to be deployed). If direct connect management tools are to be used (e.g. Telnet), it may be necessary to enable external management functions.
   
   
5. Check lightpath diagnostics for your BladeCenter:

   	BladeCenter (Type 8677)
   	BladeCenter JS20
   	BladeCenter HS20
   	BladeCenter HS40
   	BladeCenter T (Type 8720, 8730)

   
   
6. Consult the available product documentation:
   
   

   	4-Port Gb Ethernet Switch Module Installation and User's Guide
   	4-Port Gigabit Ethernet Switch Module product overview

   
   
   
7. If these steps have not solved your problem,
   refer to "Need more help?"
   
   

When you use the Ethernet switch module Telnet interface to request the switch module to ping something, the first ping response reports a failure, although the other repetitions might report success. This occurs regardless of whether the switch module port the pinged object is connected to is internal or external, and applies to pinging blade servers but not to pinging the management module or objects connected to its external Ethernet port, such as the network management station. To get accurate results, always specify multiple repetitions (>1) in the ping request, and ignore the first ping response from that request. See the IBM 4-Port Gb Ethernet Switch Module for BladeCenter Installation Guide for instructions on how to ping through the Telnet interface.

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If the Wake-on-LAN (WOL) feature is disabled on a blade server, and the blade server is turned off, the switch module internal port link to that blade is down. This is not an error, but the graphic of the BladeCenter unit might show a blank panel instead of a blade server in that bay.

Note: You can enable or disable the WOL feature on a blade server through the management-module Web interface or through the IBM Director console. Do not rely on the BladeCenter graphic in the Ethernet switch-module firmware Web interface to determine the presence or absence of blade servers in the BladeCenter unit.

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The time stamp on entries in the Ethernet switch module log uses elapsed time (since last switch restart). The time stamp on entries restarts from 0 each time the switch is restarted, although the entries do remain in order of occurrence.

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If an Ethernet cable is accidentally removed from the back of the BladeCenter unit, the small red X (disconnect notice) that normally would appear to indicate that the cable was disconnected will not appear in the bottom right of the screen. The disconnect notice does not appear because the blade server Ethernet controller connects to the Ethernet switch module through integrated circuitry inside the BladeCenter unit. When troubleshooting Ethernet-related problems, ensure that the Ethernet cables on the back of the BladeCenter unit are connected properly.

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When troubleshooting Ethernet-related problems, ensure that the Ethernet cables on the back of the BladeCenter unit are connected properly.

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When you use the management-module Web interface to update the Ethernet switch module configuration, the management module firmware writes its settings for the switch module only to the management module NVRAM; it does not write its settings for the switch module to the switch module NVRAM.

If the switch module restarts when the management module is not able to apply the IP address it has in NVRAM for the switch module, the switch module will use whatever IP address it has in its own NVRAM. If the two IP addresses are not the same, you might not be able to manage the Ethernet switch module any more.

The management module cannot apply the switch IP address from its NVRAM if:

• The management module is restarting
• The management module has failed
• The management module has been removed from the unit.

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