From mboxrd@z Thu Jan 1 00:00:00 1970 References:

From: Heinz Mauelshagen Message-ID: Date: Mon, 17 Aug 2020 13:29:35 +0200 MIME-Version: 1.0 In-Reply-To: Content-Type: multipart/alternative; boundary="------------A424B2E3355B08C193445884" Content-Language: en-US Subject: Re: [linux-lvm] extend raid5 - how if possible? Reply-To: LVM general discussion and development List-Id: LVM general discussion and development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , List-Id: To: LVM general discussion and development , lejeczek This is a multi-part message in MIME format. --------------A424B2E3355B08C193445884 Content-Type: text/plain; charset="utf-8"; format="flowed" Content-Transfer-Encoding: 8bit On 8/15/20 10:57 AM, lejeczek wrote: > Hi guys > > In hope that experts roam this list I want to ask if it is > possible to extend raid5. > If I wanted to be specific, raid created this way: > > $ lvcreate -n raid5.1 -l 100%pv --stripes 5 --stripe-size 8 > ST2000_front.0 /dev/sdj /dev/sdk /dev/sdn /dev/sdo /dev/sdp > /dev/sdq > > You can see I try to be specific about hard disks here. I > hope that later I can add more of exact same hard disk to > the system and extend such raid5. As you consumed all capacity on those disks, you either got the option to extend using lvextend (though you don't need the same disk sizes but you'd need 6 more disks to be able to extend all the given raid5 stripes using lvextend) -or- you can lvconvert adding stripes to your given raid5 which will also grow the RaidLV size by the added stripe capacities. In that later case of adding stripes, you'd have to deploy N additional disks (N = number of stripes to add) of the same or larger size than the ones you got. Mind, you could also convert to e.g. raid6 in case your resilience requirements change which'll require another disk to store parity blocks. Heinz > > many thanks, L. > > _______________________________________________ > linux-lvm mailing list > linux-lvm@redhat.com > https://www.redhat.com/mailman/listinfo/linux-lvm > read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/ --------------A424B2E3355B08C193445884 Content-Type: text/html; charset="utf-8" Content-Transfer-Encoding: 8bit

On 8/15/20 10:57 AM, lejeczek wrote:

Hi guys

In hope that experts roam this list I want to ask if it is
possible to extend raid5.
If I wanted to be specific, raid created this way:

$ lvcreate -n raid5.1 -l 100%pv --stripes 5 --stripe-size 8
ST2000_front.0 /dev/sdj /dev/sdk /dev/sdn /dev/sdo /dev/sdp
/dev/sdq

You can see I try to be specific about hard disks here. I
hope that later I can add more of exact same hard disk to
the system and extend such raid5.

As you consumed all capacity on those disks, you either got the option to extend using lvextend (though you don't need the same disk sizes but you'd need 6 more disks to be able to extend all the given raid5 stripes using lvextend) -or- you can lvconvert adding stripes to your given raid5 which will also grow the RaidLV size by the added stripe capacities. In that later case of adding stripes, you'd have to deploy N additional disks (N = number of stripes to add) of the same or larger size than the ones you got.

Mind, you could also convert to e.g. raid6 in case your resilience requirements change which'll require another disk to store parity blocks.

Heinz


many thanks, L.

_______________________________________________
linux-lvm mailing list
linux-lvm@redhat.com
https://www.redhat.com/mailman/listinfo/linux-lvm
read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/

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