Welcome to Dell EMC Cisco MDS 9000 ‘How To’ series
‘How to perform a basic health check on Cisco MDS 9000 switches’
Reference: Dell EMC Knowledge Base Article number 305413.
This video was created to:
Understand how to perform a general health check on a Cisco MDS switch.
The main purpose of this is to easily determine
the overall health of the switch hardware and software.
A general health check will provide:
A review of the switch syslog and exception log
for events of a specific time window.
General hardware and software failures.
General mis-configurations.
Reasons for port events will be provided
This video presents:
Switch information mainly, like the switch name, switch model, switch serial number,
Firmware version, type and number of modules installed in system time.
If the switch has encountered any interface related issues,
we can list the interface numbers along with its current status.
If there are any environmental issues found
with regards to power supply, fan and temperature.
Is there any generation of core files which is present in active supervisor?
Switch upgrade history.
How to clear the historical counters on the switch.
If the switch experiences any module exceptions, such as frame drops issues.
How to check the accounting log, to determine the accounting log contents.
How to check the switch logging log output,
which explains the current system message status.
A general health check can be performed twice in a span of a month
to understand if the switches are functioning smoothly as per best practice.
It can also be decided according to the environment needs.
Please note the list of basic commands
required to perform a general health check.
PuTTY into the switch.
Enter the switch credentials.
Let’s start performing the health check by using a few commands.
“show switchname” displays the name of the switch.
The “show hardware” command lists the switch hardware model type,
along with the status of the hardware components.
“show sprom backplane 1” lists the serial number of the switch.
“show version” command is used to check the OS version of the switch module.
The “show module” command lists the module status, along with the blade model in use.
The “show system uptime” command informs how long this switch is running
from the last reboot.
The output “show environment” command gives us the details
on power supply, fan, temperature and sensor status of the switch.
The “show interface brief” command is used to list all the interfaces in the switch,
along with its status, its speed and type of port details.
In order to determine complete interface details,
for example, slot one, port three,
the “show interface, slot number, port number” command is used.
This command displays a brief summary of the interface configuration information.
The “show interface transceiver details” command will provide information
about the transceiver or SFP connected to a specific interface.
The RX value indicates the receiving end light levels,
which is the physical cables.
The TX value indicates the SFP light levels.
One could decide the right range of light levels
by reading the range specified in the alarms and warning column.
In order to reset the historical counters, the “clear counters” command is used.
The “show module internal exception log” command explains exception information
about a particular module, consisting of device ID, device name,
device error code, device type, error number, system error code,
error type, ports affected, error description,
along with the time of the instance.
Hence, by referring to this system error code message,
we would be able to further investigate the issue.
The “show accounting log” gives us details on the user accounts,
and changes been performed on the switch, along with the time frame.
The “show logging log” output
displays the messages in the log file that were timestamped.
This output majorly helps us determine any issues occurred on the switch,
along with the error message,
which can be referred from the message reference guide
to understand what the error means and the resolution for it.
The “show logging and nvram” command
lists the messages in the nonvolatile Random Access Memory log.
The “show logging onboard starttime” command is exclusively used to determine
each module error stats, memory leak, environmental history sensor error,
slow port monitor events and TX waits.
This output gives a basic hint to determine any frame loss
or high TX wait time in the switch.
The “show core” command captures unusual switch crash
or any module switch blade crash or a software process crash.
This log file is generated and stored along with system files into a tar file.
Refer to the following for more information:
KB number 334854, which explains how to troubleshoot a Cisco slow drain device.
Also refer to the Cisco MDS 9000 Series Command Reference Guide
and the Message Reference Guide.
Thank you for watching.