Cisco Cisco IOS Software Release 12.2(55)SE

You should review this section before you begin working with the switch. These are known limitations 
that will not be fixed, and there is not always a workaround. Some features might not work as 
documented, and some features could be affected by recent changes to the switch hardware or software.

This section contains these limitations:

A static IP address might be removed when the previously acquired DHCP IP address lease expires. 

This problem occurs under these conditions:

When the switch is booted up without a configuration (no config.text file in flash memory).

When the switch is connected to a DHCP server that is configured to give an address to it (the 
dynamic IP address is assigned to VLAN 1).

When an IP address is configured on VLAN 1 before the dynamic address lease assigned to 
VLAN 1 expires.

The workaround is to reconfigure the static IP address. (CSCea71176 and CSCdz11708)

When connected to some third-party devices that send early preambles, a switch port operating at 
100 Mb/s full duplex or 100 Mb/s half duplex might bounce the line protocol up and down. The 
problem is observed only when the switch is receiving frames. 

The workaround is to configure the port for 10 Mb/s and half duplex or to connect a hub or a 
nonaffected device to the switch. (CSCed39091)