Troubleshooting port or interface problems on switches

Troubleshooting port or interface problems on switches

CatOS Commands	Cisco IOS Commands	Description
show version	show version	switches  running CatOS, this command displays software and hardware version info per module and system memory sizes.  For switches that run Cisco IOS, this command displays output similar to a Cisco router, like software image name and version information and system memory sizes.
show module	show module	this command displays what cards are present in the switch, the version of software they are that run, and what state the modules are in: ok, faulty, etc.  Helpful in diagnosing a hardware problem on a module or port.
show config	show that run-config	For CatOS, this command displays the non-default configuration settings of the switch (all changes made to the default configuration). All changes to the config in CatOS are saved automatically.  For Cisco IOS, this command displays the current configuration file of the switch. Changes are saved to the config in Cisco IOS with the write memory command.  Helpful in determining whether a misconfiguration of the mod/port or interface, can cause a problem.
show port	show interfaces	For CatOS , the show port command displays whether the port is connected, what VLAN it is in, what speed/duplex it is that run at, channel information, errors, etc.  For Cisco IOS, the show interfaces command displays the administrative and operational status of a switching port, input and output packets, buffer failures, errors, etc.
clear counters	clear counters	clear counters command is used  to zero the traffic and error counters so that you can see if the problem is only temporary, or if the counters continue to increment. Note: The Catalyst 6500/6000 series switches do not clear the bit counters of an interface with the clear counters command. The only way to clear the bit counters in these switches is to reload.
show port counters	show interfaces counters	For CatOS, the show port<mod/port> command displays port error counters like FCS, alignments, collisions, etc . For Cisco IOS on the Catalyst 6000, 4000, 3550, 2950, and and 3750 series, the equivalent command is show interfaces card-type x/y counters errors.
show counters	show counters interface  show controllers ethernet-controller	For CatOS, the show counters command displays the 64-bit and 32-bit hardware counters for a given mod/port or interface. Counters vary dependent upon the module type and platform.  For Cisco IOS, the show counters interface command was introduced in software version 12.1(13)E for the Catalyst 6000 series only and is the equivalent of the show counters command for CatOS which displays 32-bit and 64-bit error counters.  For Cisco IOS on 2900/3500XL, 2950/2955, 3550, 2970 and 3750 series switches, the show controllers Ethernet-controller command is used.  Displays discarded frames, deferred frames, alignment errors, collisions, etc.
show test	show diagnostic(s)  show post	For CatOS, the show test command displays any hardware errors encountered on startup.  For Cisco IOS, the equivalent command is show diagnostic which was introduced in 12.1(11b)E for the Catalyst 6000 series and show diagnostics(with an s) which was introduced in for the Catalyst 4000 Series. Both commands display Power-On Self Test (POST) results.  For Cisco IOS on the 2900/3500XL, 2950/2955, 3550, 2970 and 3750 series switches, the equivalent command is show post which displays the results of the switch POST.