Re: mdadm.conf questions

[Herta Van den Eynde <herta.vandeneynde@cc.kuleuven.ac.be>]

Thanks for your prompt reply, Neil.

You're right - of course - about the man pages.  Only, if you're new to 
this, it's not always evident to determine what constitutes "unwanted 
detail".  Thanks for explaining.

Kind regards,

Herta

Neil Brown wrote:

>On Thursday May 15, herta.vandeneynde@cc.kuleuven.ac.be wrote:
>  
>
>>When I run "mdadm --detail --scan", the command outputs information about the devices in the array on a separate line:
>>
>># mdadm --detail --scan
>>ARRAY /dev/md3 level=raid0 num-devices=3 UUID=fc5d996b:15107473:e3e819c9:6829a450
>>   devices=/dev/md0,/dev/md1,/dev/md2
>>ARRAY /dev/md2 level=raid1 num-devices=2 UUID=32d034b8:e93cc8c7:f6335e14:829aefee
>>   devices=/dev/sde,/dev/sdh
>>ARRAY /dev/md1 level=raid1 num-devices=2 UUID=4efa3017:9dc3fa9b:6f4acac4:e1944bec
>>   devices=/dev/sdd,/dev/sdg
>>ARRAY /dev/md0 level=raid1 num-devices=2 UUID=1d078c62:2b90a2c3:1ec1d0af:75600395
>>   devices=/dev/sdc,/dev/sdf
>>
>>1. When I redirect this output to '/etc/mdadm.conf, should I then
>>edit the file to join the line listing the devices to the one
>>defining the ARRAY? 
>>    
>>
>
>Only if you want to.  mdadm is happy with continuing a line in the
>next line if it is indented.
>
>  
>
>>2. Should the devices tag be there at all?  sd[c-e] are on a
>>separate bus from sd[f-h].  If I add more devices to the first bus,
>>sd[f-h] will be renamed.  Won't that confuse the md driver?  
>>    
>>
>
>No, the device tag normally is not needed.  I think the man page makes
>a point of saying that the output of --detail --scan is only the
>starting point of an mdadm.conf.  You need to edit it based on how
>your system is managed.  In some cases, e.g. ide drives, a devices
>entry is a good idea.  In most cases, and particularly with SCSI it
>isn't.
>
>  
>
>>3. should I add /dev/md[0-2] as DEVICE in /etc/mdstat.conf?
>>    
>>
>
>Yes.
>
>NeilBrown
>  
>