Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.
Summary: help with dd! Felix Frank wrote: > On 06/03/2011 11:06 AM, Sebastian wrote: >> I presume that to do this I would need to break my existing DRBD >> set-up and possibly lose all the data on it? How can I do this >> without losing the data? Can I make the cluster stand-alone, >> reconfigure one of the nodes to use an LVM Volume as my backing >> device, make that one the primary, wait until it resyncs, do the >> same on the other node, then extend the DRBD device, and then extend >> the filesystem? > > What is the current layout and DRBD usage? <reposted this part (sizes slightly edited) for ease of reference> DRBD is being used as part of Openfiler to produce a HA cluster for NAS storage. The current layout on node1 is: /dev/sda ~ 8 GB - O/S disk /dev/sdb1 ~ 512 MB - /dev/drbd0 - used for cluster_metadata /dev/sdb2 ~ 1TB-512MB - /dev/drbd1 (actually LVM so /dev/mapper/vg0drbd-filer) - used for NAS /dev/sdc1 ~ 1 TB - /dev/mapper/tempnas-tempnasv LV - temporary storage, has 90% of the data contained on /dev/sdb2 - I want to reformat this disk and add it to /dev/drbd1, well /dev/mapper/vg0drbd-filer. The current layout on node2 is: /dev/sda ~ 8 GB - O/S disk /dev/sdb1 ~ 512 MB - /dev/drbd0 - used for cluster_metadata /dev/sdb2 ~ 1TB-512MB - /dev/drbd1 (actually LVM so /dev/mapper/vg0drbd-filer) - used for NAS /dev/sdc1 ~ 1 TB - unformatted. </end repost> > You could get away with doing this online. > > 1. Create VG on secondary (with free disks, assuming you have those) > 2. take secondary offline, dd everything to an LV in the new VG I've done #1, took secondary offline, and trying dd: [root at Openfiler2 etc]# dd if=/dev/vg0drbd/filer of=/dev/local/r1 dd: opening `/dev/vg0drbd/filer': No such file or directory I tried making the old vg (vg0drbd) available, but that didn't help: [root at Openfiler2 etc]# lvdisplay --- Logical volume --- LV Name /dev/local/r1 VG Name local LV UUID e61tb2-FkVu-j3mv-OLJ5-EFOl-ClWY-xx59RN LV Write Access read/write LV Status available # open 0 LV Size 975.93 GiB Current LE 249837 Segments 1 Allocation inherit Read ahead sectors auto - currently set to 256 Block device 253:0 --- Logical volume --- LV Name /dev/vg0drbd/filer VG Name vg0drbd LV UUID eSuNJr-yFDC-WCET-sIgi-IgTf-JRYz-Ack7oe LV Write Access read/write LV Status available # open 0 LV Size 975.41 GiB Current LE 249704 Segments 1 Allocation inherit Read ahead sectors auto - currently set to 256 Block device 253:1 N.B. The difference in size is due to the 512 MB partition in sdb1. So sdc1 is larger than sdb2 by around 512 MB. Given this difference in size, am I ok to clone using dd? I presume I will need to resize the filesystem to the slightly larger partition size (and then I will need to do it again after adding the other LV). Instead of the above dd, do I need to use something like: [root at Openfiler2 etc]# dd if=/dev/sdb2 of=/dev/sdc1 ? Or will that clone the LVM stuff like the LV UUID and whatever else LVM writes? The examples I have seen are like this: [root at Openfiler2 etc]# dd if=/dev/sdb of=/dev/sdc But I don't need to clone the entire drive. sdb1 is fine how it is. It is being used as /cluster_metadata under a separate DRBD resource. > 3. bring secondary back, using the new LVM backing device > 4. promote secondary, repeat on former primary > 5. scrub former backing devices, include in VG and expand LVs > as desired > 6. resize the DRBD as explained in the User's Guide > > Cheers, > Felix Kind regards, Sebastian