[dm-devel] you cannot run this tool with these options on live metadata

[Khitai Pang]

Hi,

After creating a LVM cache LV, I have the following devices in /dev/mapper:

MyCache-CacheDataLV_cdata
MyCache-CacheDataLV_cmeta
MyCache-OriginLV
MyCache-OriginLV_corig

I want to use cache_check to check the cache metadata:

# cache_check /dev/mapper/MyCache-CacheDataLV_cmeta
syscall 'open' failed: Device or resource busy
Note: you cannot run this tool with these options on live metadata.

The same issue is seen when I try to use era_check to check the metadata 
device of an era target.

How to 'offline' the cache/metadata device?


Thanks
Khitai