How to do if VSU cannot be established successfully?

Fault phenomenon
1. Device VSU cannot be established
Networking Topology




Possible Reasons
1. Device version is inconsistent
2. The device has not switched to VSU state
3. VSU configuration error (including domain ID , device ID, etc.)
4. VSL link port exception
Troubleshooting steps
1. Basic information confirmation
1.1 Check whether the device version and model are consistent.
You can use 'show ver' to check the specific device model and version. If the version is inconsistent, the VSU may can't be built.



1.2 Check if the VSU configuration is correct
You can use 'show switch virtual config' to check device VSU configuration
Check: whether the domain ID is consistent, whether the switch ID is inconsistent, and whether the vsl link port is correct





If the domain ID is inconsistent / switch ID isconsistent/ VSL link port configuration is abnormal, it will cause the VSU to fail to build.
Such as: Device Switch ID consistent
Configure the Switch ID of the two switches to beconsistent, and the switch information that failed the election cannot beviewed by the VSU master device.
Both devices are ACTIVE







2. Confirm whether the VSU device is in VSU mode
You can use 'show switch virtual' to check the device vsu status




If one of the VSU devices is in standalone state, the VSU cannot be established
3. Confirm VSL link is abnormal
Using 'show int xxx' to check whether the VSL port status is normal and whether there are abnormal phenomena such as error packet loss undert he interface



Using 'show int xx tran' to check if the vsl link port receives light attenuation normally



Using 'show switch virtual link'. The state shows up to indicate that the status is normal.



Using 'show switch virtual link port' to check if the VSL link status is normal.
"DOWN" means the current port physical isLINK DOWN;
"DISABLE" indicates that the current porthas an error frame;
"UP" indicates that the current port isphysically LINK UP, but it has not been detected that the other end is a validVSL-AP member port;
"OK" indicates that the port is not onlyphysically LINK UP, but also detects that the peer is a valid VSL-AP memberport.



Information Collection
1. Use full script tocollect directly
2. Collect the following information when unable touse the full script:
Show ver
Show ver detail
Show sw for conf
Show sw for
Show int
Show int tran
show switch virtual link
show switch virtual link port
Show run
Show log
Summary and Recommendations
Generally, the wrong configurations of switchesare the main causes of VSU exceptions.