Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.
Thank you, Leonardo, this is very helpful! I have a better understanding now, but one more question: On Thursday 02 February 2006 11:00, Leonardo Rodrigues de Mello wrote: > Hi Nate, > -----Mensagem original----- > > >De: drbd-user-bounces at lists.linbit.com em nome de Nate Reed > >Enviada: qui 2/2/2006 14:41 > >Para: General Linux-HA mailing list > >Cc: drbd-user at lists.linbit.com > >Assunto: [DRBD-user] software RAID, LVM > > > >Here's what I was thinking of doing on each machine: > > > >disk 1 > > - swap partition > > - / partition > > - Linux RAID partition > > > >disk 2 > > - Linux RAID partition I wonder if I could refine this scheme to add redundancy of / and swap as follows: disk 1 - RAID 1 (md0) - RAID 2 (md1) disk 2 - RAID 1 (md0) - RAID 2 (md1) Create two RAID devices, for example: /dev/md0 (for disk1/RAID1 and disk 2/RAID 1) and /dev/md1 (for disk 1/RAID 2, and disk 2/RAID2). DRBD would access /dev/md0, and there are LV's / and swap on /dev/md1. This should insulate LVM against failure of one of the disks. What do you think of this? Nate > > > >Then, create a RAID device out of the two Linux RAID partitions, then put > > >DRBD on top of this device > > Good aproach. this is what i had done with success. > > >The other setup I was considering is: > > > >disk 1 > > - Linux RAID partition > > > >disk 2 > > - Linux RAID partition > > > >Then, create a RAID device out of these partitions, and create logical > >volumes /, swap, /shared, etc. Then, have DRBD replicate one of these > >volumes. > > if your volumes are compose of raid devices you bypass the lvm failure > limitation. > > >Finally, there is a 3rd option, but I'm not sure this makes any sense: as > >above, put logical volumes /, swap, /shared, etc., on the RAID device, and > >use DRBD to replicate the entire device to the other node. This doesn't > > make much sense since some data -- esp. swap -- should be local to each > > machine. > > Doenst make sense :-D > > >So, what do you think? > > > >1. Have DRBD replicate a logical volume (/shared). Is this possible? Is > >there a block device associated with a lv? > > Yes there is... if doenst have, you cant format it and use as a physical > disk. > > >2. Have DRBD replicate a /shared partition on RAID, and keep swap and / on > >disk #1. Obvious downsides: no redundancy of swap and root, and wasted > > space on disk #2. > > You will have to apply patchs to your system inicialization, to mount your > DRBD partition before starting anything, i didnt done this yet, but believe > its possible. > > >Am I missing some other approach? > > > >Thanks, > >Nate > >_______________________________________________