 |
Notes on Setting up RAID and Related Issues
Russell Bateman |
Table of Contents
- Introduction
- ZFS on Linux
- Some documents about ZFS
- RAID notes
- mdadm
- ZFS practical
- Server installation
- Pre-launch maintenance
- And now, for zfs
- Steps
- zfs terminology
- Beginning the serious work...
- We get down to it...
- Starting over...
- Appendices
Introduction
I decided to lose my VMware ESXi server set-up as, with my latest employment, I simply don't need the technology and I don't have time to use it at home for now. So, I've got this machine (see here and here) freed up on which to set up my new Plex Media server and want to do a RAID 1 thingy.
First, taking into account the notes at the bottom on (just plain) RAID, my assortment of disks isn't too promising for mirroring:
- 2Tb WD—empty
- 2Tb WD—empty
- 4Tb Seagate—empty
- 1Tb Seagate—already holding all (circa 300Gb) of my present, Plex-entrusted media*
(* would be nice not to have to back this up and restore it.)
Other details on the machine I'm using:
- Intel i5-2500K 6Mb L3, 1Mb L2, 3.3GHz
- 16Gb memory
I'll have to see what I can make of it all.
ZFS on Linux
This was some early work on documenting ZFS. Don't pay too much attention until the "practical" stuff that illustrates some horsing around I did before settling on a final approach, documented in Setting up tol-eressëa.
60,000' overview
https://en.wikipedia.org/wiki/ZFS
Third-party demonstration of installation on Debian
Really, really good treatment. I may just follow this guy's write-up and skip the head-scratching.
FAQ
http://zfsonlinux.org/faq.html
Formal documentation for Debian
https://pthree.org/2012/04/17/install-zfs-on-debian-gnulinux/
mdadm
mdadm is at least as old as 2005. Not sure this is the road I want to walk. Anyway, even if it did a good job and wasn't hard to manage, my first disks were all of different sizes and useless for RAID 1.
- http://linuxconfig.org/linux-software-raid-1-setup
- http://www.dedoimedo.com/computers/linux-raid.html
RAID notes in general
RAID 0
With RAID 0, the RAID controller tries to evenly distribute data across all disks in the RAID set.
Envision a disk as if it were a plate, and think of the data as a cake. You have four cakes—chocolate, vanilla, cherry and strawberry—and four plates. The initialization process of RAID 0, divides the cakes and distributes the slices across all the plates. The RAID 0 drivers make the operating system feel that the cakes are intact and placed on one large plate. For example, four 9Gb hard disks configured in a RAID 0 set are seen by the operating system to be one 36Gb disk.
RAID 0 can accommodate disks of unequal sizes.
The advantage of RAID 0 is data access speed and viewing several disks as one filesystem. A file that is spread over four disks can be read four times as fast. RAID 0 is often called striping.
RAID 1
Data is cloned on a duplicate disk. This RAID method is therefore frequently called disk mirroring. Think of telling two people the same story so that if one forgets some of the details you can ask the other one to remind you.
A limitation of RAID 1 is that the total RAID size in gigabytes is equal to that of the smallest disk in the RAID set. Unlike RAID 0, the extra space on the larger device isn't used.
RAID 4
Operates likes RAID 0 but inserts a special error-correcting or parity chunk on an additional disk dedicated to this purpose.
RAID 4 requires at least three disks in the RAID set and can survive the loss of a single drive only. When this occurs, the data in it can be recreated on the fly with the aid of the information on the RAID set's parity disk. When the failed disk is replaced, it is repopulated with the lost data with the help of the parity disk's information.
RAID 4 combines the high speed provided by RAID 0 with the redundancy of RAID 1. Its major disadvantage is that the data is striped, but the parity information is not. In other words, any data written to any section of the data portion of the RAID set must be followed by an update of the parity disk. The parity disk can therefore act as a bottleneck. For this reason, RAID 4 isn't used very frequently.
RAID 5
Improves on RAID 4 by striping the parity data between all the disks in the RAID set. This avoids the parity disk bottleneck, while maintaining many of the speed features of RAID 0 and the redundancy of RAID 1. Like RAID 4, RAID 5 can survive the loss of a single disk only.
ZFS practical
Here are some resources I resorted to through this process.
- Ubuntu wiki ZPool
- A hands-on introduction to zfs pools using a bunch of thumb drives.
- What to call ZFS vdev that won't change?
- 1.9 How do I set up the /etc/zfs/vdev_id.conf file?. I elected not to much with this, but just use /dev/disks instead.
- zfs tutorial
- zfs: How to create pool of two existing vdevs, then mount it
- Creating and Destroying ZFS Storage Pools
zfs is a highly scalable, future-proof filesystem and logical volume manager designed around the concepts that a) data integrity is paramount, storage administration should be simple and c) everything can be done on-line.
We're setting up zfs, the special filesystem that will allow me to mirror each of the two drive pairs (2 Tb and 4 Tb), then group them together as if one big 6 Tb drive.
The idea is that if an drive goes bad, its mate will still have all the data on it and the system doesn't skip a beat. I will just need to buy a new drive of the same size and replace the bad on before the surviving one ever goes bad.
Here are the Ubuntu stable release of zfs. However, this page is not meticulously helpful. Please follow these instructions instead.
Steps
- An
article I read, suggested doing this:
# apt-get install python-software-properties - Add the ppa:zfs-native/stable personal package archive (PPA) to
system and update the latest list of software with that:
# add-apt-repository ppa:zfs-native/stable (fetches keys) The native ZFS filesystem for Linux. Install the ubuntu-zfs package. This PPA contains the latest stable release. Please join the Launchpad user group if you want to show support for ZoL: https://launchpad.net/~zfs-native-users The ZoL project home page is: http://zfsonlinux.org/ Send feedback or requests for help to this email list: <email address hidden> A searchable email list history is available at: http://groups.google.com/a/zfsonlinux.org/group/zfs-discuss/ Report bugs at: https://github.com/zfsonlinux/zfs/issues Get recent daily beta builds at: https://launchpad.net/~zfs-native/+archive/daily Press [ENTER] to continue or ctrl-c to cancel adding it gpg: keyring `/tmp/tmpyi8f5o2m/secring.gpg' created gpg: keyring `/tmp/tmpyi8f5o2m/pubring.gpg' created gpg: requesting key F6B0FC61 from hkp server keyserver.ubuntu.com gpg: /tmp/tmpyi8f5o2m/trustdb.gpg: trustdb created gpg: key F6B0FC61: public key "Launchpad PPA for Native ZFS for Linux" imported gpg: Total number processed: 1 gpg: imported: 1 (RSA: 1) OK # apt-get update
- As I'll want to upgrade zfs when necessary, I elected to create
/etc/apt/sources.list.d/zfs.list with these contents.
# vim /etc/apt/sources.list.d/zfs.list deb http://ppa.launchpad.net/zfs-native/stable/ubuntu trusty main deb-src http://ppa.launchpad.net/zfs-native/stable/ubuntu trusty mainIf you get something like the following, it's because you failed to perform the step to add the PPA to the repository successfully:
W: GPG error: http://ppa.launchpad.net trusty Release: The following signatures couldn't be verified \ because the public key is not available: NO_PUBKEY 1196BA81F6B0FC61 - The command to install zfs is here; it takes a very long time (in excess
of 10 minutes), there's lots of installing prerequisites, linking, etc.
# apt-get install ubuntu-zfs
Initial tuning
This is listed as a step for Linux installations by an article I read. Apparently, we must limit zfs' advanced replacement cache (ARC) to an appropriate value otherwise it's too slow to release RAM back to the processor and will starve system memory. The article advises setting it at one-half of the total system RAM. In our case, this is 8 Gb. As it has to be in bytes, there's a comment that gives several useful values.
This is done in /etc/modprobe.d/zfs.conf. Here's mine; this file didn't exist before I created it.
# /etc/modprobe.d/zfs.conf # # yes you really DO have to specify zfs_arc_max IN BYTES ONLY! # 16GB=17179869184, 8GB=8589934592, 4GB=4294967296, 2GB=2147483648, 1GB=1073741824 # options zfs zfs_arc_max=8589934592
I plan on rebooting to make this value effective. After reboot, I see this confirming that I successfully established the maximum number of bytes the ARC can monopolize at any given time to 8 Gb.
root@tol-eressea:/# grep c_max /proc/spl/kstat/zfs/arcstats
c_max 4 8589934592
zfs terminology
By zfs, data stored is on one or more vdevs (virtual device), which may populate one or more higher-level vdevs. In my case, I predict something like the illustration below, we'll see how well I understood as we go.
A vdev can be a single, physical drive or even partition. In my case, the lowest granularity will be a physical drive. Or, it can be a higher-level concept consisting of multiple drives or partitions.
We'll use something called a zpool to subsume the 2 mirrored vdevs into a RAID10 array logically mapping the 2 Tb and 4 Tb vdevs into one 6 Tb entity.
vdevs are immutable: once created, they cannot be added to. zpools are not: I can add more mirrored vdevs to my pool as needed using zpool add.
What's important in the behavior of a zpool is that the system will try to fill up the vdevs in a balanced way as much as possible. To see the zpool status, do this.
# zpool status
pool: Avallonea
state: ONLINE
scrub: none requested
config:
NAME STATE READ WRITE CKSUM
aquilonde ONLINE 0 0 0
mirror-0 ONLINE 0 0 0
wwn-0x50014ee2080259c8 ONLINE 0 0 0
wwn-0x50014ee2080268b2 ONLINE 0 0 0
mirror-1 ONLINE 0 0 0
wwn-0x50014ee25d4cdecd ONLINE 0 0 0
wwn-0x50014ee25d4ce711 ONLINE 0 0 0
(The wwn-... stuff is fictional for now.) As implied, each vdev will contain the same percentage of data as the other. In my case, for 4 Gb of data written, zfs will try to put roughly 1.3 Gb on (2 Tb) mirror-0 (the Western Digital pair) and 2.7 Gb on (4 Tb) mirror-1 (the Seagate pair).
Beginning the serious work...
Before attempting a zpool, let's get a list of the drives the system thinks it knows about.
root@tol-eressea:/# ls -l /dev/disk/by-id total 0 lrwxrwxrwx 1 root root 9 Jul 25 19:59 ata-ASUS_DRW-24B1ST_c_CAD0CL247932 -> ../../sr0 lrwxrwxrwx 1 root root 9 Jul 25 19:59 ata-ST3320613AS_6SZ27HJQ -> ../../sdc lrwxrwxrwx 1 root root 10 Jul 25 19:59 ata-ST3320613AS_6SZ27HJQ-part1 -> ../../sdc1 lrwxrwxrwx 1 root root 10 Jul 25 19:59 ata-ST3320613AS_6SZ27HJQ-part2 -> ../../sdc2 lrwxrwxrwx 1 root root 10 Jul 25 19:59 ata-ST3320613AS_6SZ27HJQ-part5 -> ../../sdc5 lrwxrwxrwx 1 root root 9 Jul 25 19:59 ata-ST4000DM000-1F2168_S300ELBZ -> ../../sde lrwxrwxrwx 1 root root 9 Jul 25 19:59 ata-ST4000DM000-1F2168_S300MZ7G -> ../../sdd lrwxrwxrwx 1 root root 9 Jul 25 19:59 ata-WDC_WD20EARX-00PASB0_WD-WCAZAJ004702 -> ../../sda lrwxrwxrwx 1 root root 9 Jul 25 19:59 ata-WDC_WD20EARX-00PASB0_WD-WCAZAJ069805 -> ../../sdb lrwxrwxrwx 1 root root 10 Jul 25 19:59 dm-name-tol--eressea--vg-root -> ../../dm-0 lrwxrwxrwx 1 root root 10 Jul 25 19:59 dm-name-tol--eressea--vg-swap_1 -> ../../dm-1 lrwxrwxrwx 1 root root 10 Jul 25 19:59 dm-uuid-LVM-bZfC1RqhLUtA1WXEM9ZDp0OrYWL7UDA90DCf3JdnKoqszQLFuQ8UYdhEIqipYTbe -> ../../dm-1 lrwxrwxrwx 1 root root 10 Jul 25 19:59 dm-uuid-LVM-bZfC1RqhLUtA1WXEM9ZDp0OrYWL7UDA9JnUvrNm3NhEWfiRBdOcmwD8xzmr3Uhi3 -> ../../dm-0 lrwxrwxrwx 1 root root 9 Jul 25 19:59 wwn-0x5000c50013f7f83d -> ../../sdc lrwxrwxrwx 1 root root 10 Jul 25 19:59 wwn-0x5000c50013f7f83d-part1 -> ../../sdc1 lrwxrwxrwx 1 root root 10 Jul 25 19:59 wwn-0x5000c50013f7f83d-part2 -> ../../sdc2 lrwxrwxrwx 1 root root 10 Jul 25 19:59 wwn-0x5000c50013f7f83d-part5 -> ../../sdc5 lrwxrwxrwx 1 root root 9 Jul 25 19:59 wwn-0x5000c5006d9b71cb -> ../../sde lrwxrwxrwx 1 root root 9 Jul 25 19:59 wwn-0x5000c5007490cd1d -> ../../sdd lrwxrwxrwx 1 root root 9 Jul 25 19:59 wwn-0x50014ee2076548d3 -> ../../sdb lrwxrwxrwx 1 root root 9 Jul 25 19:59 wwn-0x50014ee2b21019d9 -> ../../sda
Above, I recognize some names and, to make this more visible, have associated some color with the drives and I will keep this color association throughout this document:
| ASUS_DRW-24B1ST_c_CAD0CL247932 | The system DVD-RW drive | (we won't touch this drive) |
| ST3320613AS_6SZ27HJQ | This is the system drive (320 Gb) | (we won't touch these partitions) |
| WDC_WD20EARX-00PASB0_WD-WCAZAJ etc. | These are the original 2 Tb drives | Mirror these two drives |
| ST4000DM000-1F2168_S300 etc. | These are the new 4 Tb drives | Mirror these two drives |
The other stuff looks similar to the wwn- designations in the sample zpool status I copied from the article. I also recognize sda, sdb, ... sde. The article tells us that drives can be referred to multiple ways, a) by wwn id, b) by model and serial number as connected to the ATA bus, c) ditto as connected to the virtual, SCSI bus. The article says that the best designation to pick is one reproduced physically on a label on the physical drive. When one goes south, I'll want to be able to identify it, pull it out, then replace it.
I'll have to decide this soon. On my 320 Gb drive, the wwn designation is clearly visible, but the shortest designation is the model plus serial number. Maybe that's best to use.
We get down to it
For this, I had to resort to different resources because the first article, although a really fine one, only mentioned mirroring, but did not show how to set even a simple case up. That article was really good for explaining, useless for showing.
Overall, it took a while to get the commands right and the tutorials are not perfectly helpful since written by people who get it and who don't get not getting it, so they skip explaining or showing. I ended up creating two, mirrored vdevs and wanting to put them into a pool,
root@tol-eressea:/# zpool create vol1 mirror /dev/sda /dev/sdb root@tol-eressea:/# zpool create vol2 mirror /dev/sdd /dev/sde
Then I thought to combine those two vdevs into a pool.
root@tol-eressea:/# zpool create -m /plex-server aquilonde vol1 vol2 cannot open 'vol1': no such device in /dev must be a full path or shorthand device name root@tol-eressea:/# zpool create aquilonde vol1 vol2 cannot open 'vol1': no such device in /dev must be a full path or shorthand device name
...but that's not how it works. The pool is created at the same time and not separately afterward. So, I had to remove the two original vdevs I created during my trials:
It appears that instead of building from the ground-up, zfs was designed to build from halfway up the ladder down, then off to the side. Clearly object orientation wasn't in the minds of the conceivers. I'll have to deconstruct everything I've done and start over.
root@tol-eressea:~# zpool destroy vol2 root@tol-eressea:~# zpool destroy vol1 root@tol-eressea:~# zpool status no pools available
Starting over...
Now the right commands seem to be these. Notice how, instead of creating both bottom-level vdevs, we instead create the pool with unnamed vdevs we declare and mirror at the same time. We could do this all in one command, but I've used the add option to allow me to do it in two commands. Finally, we make zfs tell the filesystem about it.
First, let's create pool aquilonde with our first pair of mirrored drives.
root@tol-eressea:~# zpool create aquilonde mirror /dev/sda /dev/sdb root@tol-eressea:~# zpool status pool: aquilonde state: ONLINE scan: none requested config: NAME STATE READ WRITE CKSUM aquilonde ONLINE 0 0 0 mirror-0 ONLINE 0 0 0 sda ONLINE 0 0 0 sdb ONLINE 0 0 0 errors: No known data errors
So far, so good. Next, we'll add the second pair of mirrored drives.
root@tol-eressea:~# zpool add aquilonde mirror /dev/sdd /dev/sde root@tol-eressea:~# zpool status pool: aquilonde state: ONLINE scan: none requested config: NAME STATE READ WRITE CKSUM aquilonde ONLINE 0 0 0 mirror-0 ONLINE 0 0 0 sda ONLINE 0 0 0 sdb ONLINE 0 0 0 mirror-1 ONLINE 0 0 0 sdd ONLINE 0 0 0 sde ONLINE 0 0 0 errors: No known data errors
It's suggested giving better names than /dev/sdN, etc. since when a disk dies, it might be challenging to figure out which physical disk corresponds to the dead one. Only, it appears you can't first create vdevs using arbitrary names since zpool has to know which disk(s) you are making vdevs. Therefore, first you create using /dev/sdN, then you export the pool to a file, then import it telling it to use the naming from /dev/disk. (I'm keeping the coloring throughout this document to remind me of which disk set is the one in question.)
The last step in setting up a zfs pool is to fix up the naming so that when a drive goes bad, it's not too hard to correlate the observation that a drive is bad with the physical piece of equipment that is the drive.
root@tol-eressea:~# zpool export aquilonde root@tol-eressea:~# zpool import -d /dev/disk/by-id aquilonde root@tol-eressea:~# zpool status pool: aquilonde state: ONLINE scan: none requested config: NAME STATE READ WRITE CKSUM aquilonde ONLINE 0 0 0 mirror-0 ONLINE 0 0 0 ata-WDC_WD20EARX-00PASB0_WD-WCAZAJ004702 ONLINE 0 0 0 ata-WDC_WD20EARX-00PASB0_WD-WCAZAJ069805 ONLINE 0 0 0 mirror-1 ONLINE 0 0 0 ata-ST4000DM000-1F2168_S300MZ7G ONLINE 0 0 0 ata-ST4000DM000-1F2168_S300ELBZ ONLINE 0 0 0 errors: No known data errors
The last practical step is to instantiate the pool in the host's filesystem. Check out the command, the result and the diskspace now available to Plex. This is mirrored space!
root@tol-eressea:~# zfs set mountpoint=/plex-server aquilonde root@tol-eressea:~# ll /plex-server total 13 drwxr-xr-x 2 root root 2 Jul 27 08:48 ./ drwxr-xr-x 23 root root 4096 Jul 27 09:00 ../ root@tol-eressea:/# /home/russ/diskspace.sh Filesystem on disk: / (device: /dev/mapper/tol--eressea--vg-root) Total disk size: 278Gb Used space: 1.9Gb (1%) Free space: 262Gb Filesystem on disk: /sys/fs/cgroup (device: none) Total disk size: 4.0Kb Used space: 0b (0%) Free space: 4.0Kb Filesystem on disk: /dev (device: udev) Total disk size: 7.7Gb Used space: 4.0Kb (1%) Free space: 7.7Gb Filesystem on disk: /run (device: tmpfs) Total disk size: 1.6Gb Used space: 672Kb (1%) Free space: 1.6Gb Filesystem on disk: /sys/fs/cgroup (device: none) Total disk size: 4.0Kb Used space: 0b (0%) Free space: 4.0Kb Filesystem on disk: /sys/fs/cgroup (device: none) Total disk size: 4.0Kb Used space: 0b (0%) Free space: 4.0Kb Filesystem on disk: /sys/fs/cgroup (device: none) Total disk size: 4.0Kb Used space: 0b (0%) Free space: 4.0Kb Filesystem on disk: /boot (device: /dev/sdc1) Total disk size: 236Mb Used space: 66Mb (30%) Free space: 158Mb Filesystem on disk: /plex-server (device: aquilonde) Total disk size: 5.4Tb Used space: 128Kb (1%) Free space: 5.4Tb
I need to test out the mirroring, but so far, it's the sweet smell of success.
Changing direction a bit...
Despite the extreme convenience of having both mirrors united together as one volume in my host filesystem, it occurs to me that copying a movie to that volume would result in zfs striping it across both disks (and their mirrors) robbing my disks of their autonomy. So, I'm destroying the pool and making two pools again, the larger for television episodes and the smaller for movies.
I choose the bigger volume for television series because they seem to take up more space quicker. So, still in brown for the smaller disk and, therefore, movies while in green for television shows.
root@tol-eressea:/# zpool destroy aquilonde root@tol-eressea:/# zpool status no pools available root@tol-eressea:/# zpool create movies mirror /dev/sda /dev/sdb root@tol-eressea:/# zpool create television mirror /dev/sdd /dev/sde root@tol-eressea:/# zpool status pool: movies state: ONLINE scan: none requested config: NAME STATE READ WRITE CKSUM movies ONLINE 0 0 0 mirror-0 ONLINE 0 0 0 sda ONLINE 0 0 0 sdb ONLINE 0 0 0 errors: No known data errors pool: television state: ONLINE scan: none requested config: NAME STATE READ WRITE CKSUM television ONLINE 0 0 0 mirror-0 ONLINE 0 0 0 sdd ONLINE 0 0 0 sde ONLINE 0 0 0 errors: No known data errors root@tol-eressea:/# zpool export movies root@tol-eressea:/# zpool import -d /dev/disk/by-id movies root@tol-eressea:/# zpool export television root@tol-eressea:/# zpool import -d /dev/disk/by-id television root@tol-eressea:/# zpool status pool: movies state: ONLINE scan: none requested config: NAME STATE READ WRITE CKSUM movies ONLINE 0 0 0 mirror-0 ONLINE 0 0 0 ata-WDC_WD20EARX-00PASB0_WD-WCAZAJ004702 ONLINE 0 0 0 ata-WDC_WD20EARX-00PASB0_WD-WCAZAJ069805 ONLINE 0 0 0 errors: No known data errors pool: television state: ONLINE scan: none requested config: NAME STATE READ WRITE CKSUM television ONLINE 0 0 0 mirror-0 ONLINE 0 0 0 ata-ST4000DM000-1F2168_S300MZ7G ONLINE 0 0 0 ata-ST4000DM000-1F2168_S300ELBZ ONLINE 0 0 0 errors: No known data errors root@tol-eressea:/# zfs set mountpoint=/plex-movies movies root@tol-eressea:/# zfs set mountpoint=/plex-television television root@tol-eressea:/# ll /plex-movies total 13 drwxr-xr-x 2 root root 2 Jul 30 20:55 ./ drwxr-xr-x 25 root root 4096 Jul 30 20:57 ../ root@tol-eressea:/# ll /plex-television total 13 drwxr-xr-x 2 root root 2 Jul 30 20:55 ./ drwxr-xr-x 25 root root 4096 Jul 30 20:57 ../ root@tol-eressea:/plex-movies# /home/russ/diskspace.sh . . . Filesystem on disk: /plex-movies (device: movies) Total disk size: 1.8Tb Used space: 256Kb (1%) Free space: 1.8Tb Filesystem on disk: /plex-television (device: television) Total disk size: 3.6Tb Used space: 256Kb (1%) Free space: 3.6Tb
Appendices
Disk table
Here's the map I made of the disks after system installation and before zfs. The order of these is logical and also the order you see, top to bottom, in the photo above.
| Disk | Device | Volume | Size | Use | Comments |
|---|---|---|---|---|---|
| Seagate 320 Gb ATA ST3320613AS (scsi) |
/dev/sdc1 | boot | 255 Mb | GRUB | (still has some MSDOS thing on it? harmless? still investigating) |
| /dev/sdc2 | swap | 16.8 Gb | Swap space | ||
| /dev/sdc5 | boot | 303 Gb | / | ||
| Western Digital 2 Tb ATA WDC WD20EARX-00P (scsi) |
/dev/sda | X | 1.8 Tb | X | |
| Western Digital 2 Tb ATA WDC WD20EARX-00P (scsi) |
/dev/sdb | X | 1.8 Tb | X | (still has VMware ESXi on it—will be removed by zfs) |
| Seagate 4 Tb ST4000DM000 (scsi) |
/dev/sdd | X | 3.6 Tb | X | |
| Seagate 4 Tb ST4000DM000 (scsi) |
/dev/sde | X | 3.6 Tb | X |
Disk-related status
Now, before I used zfs, yet with all the disks connected and turning, here was the output of a number of a number of commands. There are errors here associated with the two, brand new 4 Tb disks that have never had anything on them.
$ fdisk -lu Disk /dev/sda: 2000.4 GB, 2000398934016 bytes 255 heads, 63 sectors/track, 243201 cylinders, total 3907029168 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 4096 bytes I/O size (minimum/optimal): 4096 bytes / 4096 bytes Disk identifier: 0x000d048e Device Boot Start End Blocks Id System /dev/sda1 1 3907029167 1953514583+ ee GPT Partition 1 does not start on physical sector boundary. Disk /dev/sdb: 2000.4 GB, 2000398934016 bytes 255 heads, 63 sectors/track, 243201 cylinders, total 3907029168 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 4096 bytes I/O size (minimum/optimal): 4096 bytes / 4096 bytes Disk identifier: 0x00018ad7 Device Boot Start End Blocks Id System /dev/sdb1 1 3907029167 1953514583+ ee GPT Partition 1 does not start on physical sector boundary. Disk /dev/sdc: 320.1 GB, 320072933376 bytes 255 heads, 63 sectors/track, 38913 cylinders, total 625142448 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x000146f0 Device Boot Start End Blocks Id System /dev/sdc1 * 2048 499711 248832 83 Linux /dev/sdc2 501758 625141759 312320001 5 Extended /dev/sdc5 501760 625141759 312320000 8e Linux LVM Disk /dev/sdd: 4000.8 GB, 4000787030016 bytes 255 heads, 63 sectors/track, 486401 cylinders, total 7814037168 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 4096 bytes I/O size (minimum/optimal): 4096 bytes / 4096 bytes Disk identifier: 0x00000000 Disk /dev/sde: 4000.8 GB, 4000787030016 bytes 255 heads, 63 sectors/track, 486401 cylinders, total 7814037168 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 4096 bytes I/O size (minimum/optimal): 4096 bytes / 4096 bytes Disk identifier: 0x00000000 Disk /dev/mapper/tol--eressea--vg-root: 302.9 GB, 302946189312 bytes 255 heads, 63 sectors/track, 36831 cylinders, total 591691776 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x00000000 Disk /dev/mapper/tol--eressea--vg-swap_1: 16.8 GB, 16848519168 bytes 255 heads, 63 sectors/track, 2048 cylinders, total 32907264 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x00000000 $ blkid /dev/sda1: UUID="195fdacc-4891-4250-a901-241b655387b1" TYPE="ext2" /dev/sda5: UUID="5JtzN6-u6QS-Nju1-uDs5-N1Ml-WGIi-PJgOcX" TYPE="LVM2_member" /dev/mapper/tol--eressea--vg-root: UUID="359c69e9-fe56-4403-94e0-0ef569518263" TYPE="ext4" /dev/mapper/tol--eressea--vg-swap_1: UUID="87631cc8-248e-424b-a9dd-d93ee2ec74ca" TYPE="swap" $ parted -l Model: ATA WDC WD20EARX-00P (scsi) Disk /dev/sda: 2000GB Sector size (logical/physical): 512B/4096B Partition Table: gpt Model: ATA WDC WD20EARX-00P (scsi) Disk /dev/sdb: 2000GB Sector size (logical/physical): 512B/4096B Partition Table: gpt Model: ATA ST3320613AS (scsi) Disk /dev/sdc: 320GB Sector size (logical/physical): 512B/512B Partition Table: msdos Number Start End Size Type File system Flags 1 1049kB 256MB 255MB primary ext2 boot 2 257MB 320GB 320GB extended 5 257MB 320GB 320GB logical lvm Error: /dev/sdd: unrecognised disk label Error: /dev/sde: unrecognised disk label Model: Linux device-mapper (linear) (dm) Disk /dev/mapper/tol--eressea--vg-swap_1: 16.8GB Sector size (logical/physical): 512B/512B Partition Table: loop Number Start End Size File system Flags 1 0.00B 16.8GB 16.8GB linux-swap(v1) Model: Linux device-mapper (linear) (dm) Disk /dev/mapper/tol--eressea--vg-root: 303GB Sector size (logical/physical): 512B/512B Partition Table: loop Number Start End Size File system Flags 1 0.00B 303GB 303GB ext4 $ gdisk -l /dev/sda GPT fdisk (gdisk) version 0.8.8 Partition table scan: MBR: protective BSD: not present APM: not present GPT: present Found valid GPT with protective MBR; using GPT. Disk /dev/sda: 3907029168 sectors, 1.8 TiB Logical sector size: 512 bytes Disk identifier (GUID): DDFA998F-8F8A-45F7-8BAA-A9146B1FB61C Partition table holds up to 128 entries First usable sector is 34, last usable sector is 3907029134 Partitions will be aligned on 2048-sector boundaries Total free space is 3907029101 sectors (1.8 TiB) $ gdisk -l /dev/sdb GPT fdisk (gdisk) version 0.8.8 Partition table scan: MBR: protective BSD: not present APM: not present GPT: present Found valid GPT with protective MBR; using GPT. Disk /dev/sdb: 3907029168 sectors, 1.8 TiB Logical sector size: 512 bytes Disk identifier (GUID): 8B3E3422-A0CE-4293-9EE2-75C0FA58C285 Partition table holds up to 128 entries First usable sector is 34, last usable sector is 3907029134 Partitions will be aligned on 2048-sector boundaries Total free space is 3907029101 sectors (1.8 TiB) $ gdisk -l /dev/sdc GPT fdisk (gdisk) version 0.8.8 Partition table scan: MBR: MBR only BSD: not present APM: not present GPT: not present *************************************************************** Found invalid GPT and valid MBR; converting MBR to GPT format in memory. *************************************************************** Disk /dev/sdc: 625142448 sectors, 298.1 GiB Logical sector size: 512 bytes Disk identifier (GUID): C52FC97E-3717-481A-B815-70D4446C2F65 Partition table holds up to 128 entries First usable sector is 34, last usable sector is 625142414 Partitions will be aligned on 2048-sector boundaries Total free space is 4717 sectors (2.3 MiB) Number Start (sector) End (sector) Size Code Name 1 2048 499711 243.0 MiB 8300 Linux filesystem 5 501760 625141759 297.9 GiB 8E00 Linux LVM $ gdisk -l /dev/sdd GPT fdisk (gdisk) version 0.8.8 Partition table scan: MBR: not present BSD: not present APM: not present GPT: not present Creating new GPT entries. Disk /dev/sdd: 7814037168 sectors, 3.6 TiB Logical sector size: 512 bytes Disk identifier (GUID): 26A0FEB1-9BC7-420F-9763-E85084AC2E25 Partition table holds up to 128 entries First usable sector is 34, last usable sector is 7814037134 Partitions will be aligned on 2048-sector boundaries Total free space is 7814037101 sectors (3.6 TiB) $ gdisk -l /dev/sde GPT fdisk (gdisk) version 0.8.8 Partition table scan: MBR: not present BSD: not present APM: not present GPT: not present Creating new GPT entries. Disk /dev/sde: 7814037168 sectors, 3.6 TiB Logical sector size: 512 bytes Disk identifier (GUID): 14288C92-D349-42A2-B789-3659F8888C96 Partition table holds up to 128 entries First usable sector is 34, last usable sector is 7814037134 Partitions will be aligned on 2048-sector boundaries Total free space is 7814037101 sectors (3.6 TiB)