Extreme Networks ExtremeWare XOS 11.1, Manual

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Troubleshooting
ExtremeWare XOS 11.1 Concepts Guide
436
Permanent entries remain in the FDB:
If you have made a permanent entry in the FDB that requires you to specify the VLAN to which the
entry belongs and then deleted the VLAN, the FDB entry remains. Although this does not harm the
system, if you want to removed the entry, you must manually delete it from the FDB.
Default and static routes:
If you have defined static or default routes, those routes remain in the configuration independent of
whether the VLAN and VLAN IP address that used them remains. You should manually delete the
routes if no VLAN IP address is capable of using them.
You forget your password and cannot log in:
If you are not an administrator, another user having administrator access level can log in, delete your
user name, and create a new user name for you, with a new password.
Alternatively, another user having administrator access level can log in and initialize the device. This
will return all configuration information (including passwords) to the initial values.
In the case where no one knows a password for an administrator level user, contact your supplier.
Port Configuration
No link light on 10/100 Base port:
If patching from a switch to another switch, ensure that you are using a category 5 (CAT5) crossover
cable. This is a CAT5 cable that has pins 1 and 2 on one end connected to pins 3 and 6 on the other end.
Excessive RX CRC errors:
When a device that has autonegotiation disabled is connected to an Extreme Networks switch with
autonegotiation enabled, the Extreme Networks switch links at the correct speed, but in half-duplex
mode. The Extreme Networks switch 10/100 physical interface uses a method called
parallel detection to
bring up the link. Because the other network device is not participating in autonegotiation (and does
not advertise its capabilities), parallel detection on the Extreme Networks switch is able only to sense
10 Mbps versus 100 Mbps speed and not the duplex mode. Therefore, the switch establishes the link in
half-duplex mode using the correct speed.
The only way to establish a full-duplex link is either to force it at both sides, or run autonegotiation on
both sides (using full-duplex as an advertised capability, which is the default setting on the Extreme
Networks switch).
NOTE
A mismatch of duplex mode between the Extreme switch and another network device causes poor network
performance. Viewing statistics using the
show ports rxerrors
command on the Extreme Networks switch may
display a constant increment of CRC errors. This is characteristic of a duplex mismatch between devices. This is
NOT a problem with the Extreme Networks switch.
Always verify that the Extreme Networks switch and the network device match in configuration for
speed and duplex.