We have been using 3548XL switches until now, when we are about to deploy 3550 switches.
Using basically the same configuration as for the 3548XL we encountered the following problem : when the first stack (of four switches) was connected via a GBIC to the 3Com 9400 corebuilder everything worked fine. As the second stack was connected, contact with the rest of the network was lost from both switches. It was however possible to ping and telnet from one stack to the other (through the corebuilder). Removal of the GBIC connection from one of the stacks restored network connectivity for the other stack.
The switch config is as follows.
version 12.1
no service pad
service timestamps debug uptime
service timestamps log datetime
service password-encryption
service sequence-numbers
!
hostname KR14stack1-1
!
enable password 7 21235446587
!
ip subnet-zero
!
!
spanning-tree extend system-id
!
!
interface FastEthernet0/1
no ip address
duplex half
speed 10
no snmp trap link-status
no cdp enable
spanning-tree portfast
!
*** identical config for remaining ports ***
!
interface FastEthernet0/48
no ip address
duplex half
speed 10
no snmp trap link-status
no cdp enable
spanning-tree portfast
!
interface GigabitEthernet0/1
no ip address
load-interval 30
no cdp enable
!
interface GigabitEthernet0/2
no ip address
no cdp enable
!
interface Vlan1
ip address 140.32.222.127 255.255.240.0
no ip route-cache
!
ip default-gateway 140.32.222.1
ip classless
ip http server
!
!
!
no cdp run
snmp-server engineID local 800000090300000AB7356881
snmp-server community l8y38k RO
snmp-server host 140.32.205.60 public
!
line con 0
line vty 0 4
password 7 00231154514F
login
line vty 5 15
password 7 04654D071C11
login
!
end
