[linux-lvm] confused with lvm2 filter rules

[Heming Zhao]

Hello,

BTW,
Only vgextend doesn't work, which must be a bug. It looks the filter 
handling codes have bug.

Regards,
zhm

On 6/5/19 6:20 PM, Zdenek Kabelac wrote:
> Dne 03. 06. 19 v 15:03 Heming Zhao napsal(a):
>> Hello,
>>
>> I met below filter action when executed 'vgextend'.
>> why the filter take no effect on executing pvcreate or vgcreate?
> 
>> # rpm -qa | grep lvm2
>> lvm2-clvm-2.02.180-8.16.x86_64
>> lvm2-cmirrord-2.02.180-8.16.x86_64
>> lvm2-2.02.180-8.16.x86_64
>>
>> the filter rules:  (you can see all the disk in /dev/disk/by-id/ are
>> rejected)
>> # grep filter /etc/lvm/lvm.conf | grep -v "#"
>>       filter = [ "r|/dev/.*/by-path/.*|", "r|/dev/.*/by-id/.*|",
>> "r|/dev/fd.*|", "r|/dev/cdrom|", "a/.*/" ]
> 
> 
> Hi
> 
> Filter with 'a|.*|' at the end will almost always never work.
> As devices do have several names so if you reject it by one name,
> you will likely accept it with another name.
> 
> 
> So I'd highly recommend only these 2 variants that are 'easy to follow'.
> 
> 
> 1. White-list devices you want to see and add r|.*|  as the last rule.
> ^^^^^^^^^^^^^^^ most recommended.
> 
> 2. Pure list of reject rules (do not add any 'a' rule).
> 
> Regards
> 
> Zdenek
> 
> 
>