System information

Troubleshooting LAN Switching Environments 22-453
LAN Switching: Cannot Access Out-of-Band Management
LAN Switching: Cannot Access Out-of-Band Management
Symptom: The out-of-band Management Console on the LAN switch is inaccessible.
Table 22-3 outlines the problems that might cause this symptom and describes solutions to those
problems.
Table 22-3 LAN Switching: Cannot Access Out-of-Band Management
Subnet mask
configuration error
Step 1 Check to see whether you can ping the switch from a device in the same subnet.
Step 2 Check the subnet mask on the device from which you are pinging. Check the subnet
mask on the LAN switch.
Step 3 Determine whether the subnet mask on either device is incorrectly specified. If it is,
reconfigure the switch or the device, as appropriate, with the correct subnet mask.
Refer to the user guide for your LAN switch for information on how to
check and configure the subnet mask on the switch. Refer to the vendor documentation for the
other device for information on how to check and configure the subnet mask on that device.
No default gateway
specified on switch
or server
Step 1 Check whether there is a default gateway configured on the LAN switch. Check to
make sure that all servers and other end systems on the LAN have a default gateway
specification.
Step 2 If any of these devices does not have a default gateway specified, configure a default
gateway using the IP address of a router interface on the directly connected LAN.
Refer to the user guide for your LAN switch for information on how to configure a default
gateway on the switch. Refer to the vendor documentation for the other devices for information
on how to configure a default gateway on those devices.
VLAN
1
misconfiguration
Step 1 Make sure that all nodes that should communicate are attached to ports on the same
VLAN. If ports are assigned to different VLANs, the attached devices cannot
communicate.
Step 2 If a port belongs to two or more VLANs, make sure that the VLANs are connected
only by the overlapping port. If there are other connections, an unstable network
topology can be created.
Step 3 Eliminate any extraneous connections between the two VLANs.
Wrong port 25
connector option
If a switch port has two possible connectors, make sure that the physical connection matches
the one configured in the Management Console.
1 VLAN = virtual LAN
Possible
Problem Solution
Baud rate
misconfigured
Step 1 Make sure that the LAN switch and the attached terminal or modem are configured to
use the same baud rate and character format.
The autobaud feature on most switches can match the baud rate for incoming calls, but
the switch will not change from its configured rate when it is dialing out. Also, the
autobaud feature will only match a rate lower than its configured rate. When it completes
a call and disconnects, the switch returns to the last configured baud rate.
Step 2 Test the connection using different baud rates. Refer to the user guide for your LAN
switch for more information on how to attach a terminal or modem.
Possible
Problem Solution