I have a Sheeva plug running ArchLinuxArm from SD card and I'd like to backup the SD card so I can restore everything in case something goes wrong.
I'd prefer to create an archive file (rootfs.tar.gz) or image file. I found some instructions but they seem specific to ubuntu. I need something that applies to this specific distro and device for easy restoration.
Any assistance will be greatly appreciated.
I'm a novice linux admin and now responsible for the OS of a 3 node Tomcat cluster. (Tomcat is handled by the DEVs luckily.)
I got alarmed by our monitoring solution that /var on server01 has only 172MB left of free space. Most likely because /var/log did fill up.
So I investigated with:
server01:/var# for i in $(ls); do du -sh $i; done
3.5M backups
100M cache
51M lib
0 local
0 lock
598M log
0 mail
0 opt
40K run
32K spool
144K tmp
4.0K www
If I sum that up I end by something around 760MB used. The numbers don't change if I dig deeper into the directory tree. So this is correct.
But if I execute a df -h I end up with completely different numbers for /var. df shows that 2.8G out of 3.0G are used.
server01:/var# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/sda1 950M 205M 697M 23% /
tmpfs 2.0G 0 2.0G 0% /lib/init/rw
udev 2.0G 4.0K 2.0G 1% /dev
/dev/sda3 961M 33M 928M 4% /tmp
/dev/dm-0 2.0G 506M 1.5G 26% /usr
/dev/dm-1 3.0G 2.8G 172M 95% /var
/dev/dm-2 20G 17G 3.3G 84% /home
The funny thing is, that the other 2 nodes are reporting even more used spaced on /var. Because /var/log/ on node 2 and 3 are consuming 200-300MB more space. But partitions and the underlying LVM are having the same size on all 3 nodes.
On server02 and server03 df -h reports that everything is fine and only 1.0 to 1.2GB are used from 3.0GB.
So where is my space being used?
I heared of those little bastards called inodes and checked for this. df -i reports:
server01:/var# df -i
Filesystem Inodes IUsed IFree IUse% Mounted on
/dev/sda1 123648 6099 117549 5% /
tmpfs 506908 3 506905 1% /lib/init/rw
udev 506487 675 505812 1% /dev
/dev/sda3 987968 7 987961 1% /tmp
/dev/dm-0 2048000 19786 2028214 1% /usr
/dev/dm-1 705808 1807 704001 1% /var
/dev/dm-2 13619632 5906 13613726 1% /home
And on server02 and server03:
server03:/var# df -i
Filesystem Inodes IUsed IFree IUse% Mounted on
/dev/sda1 123648 6100 117548 5% /
tmpfs 506908 3 506905 1% /lib/init/rw
/dev 506487 675 505812 1% /dev
/dev/sda3 987968 7 987961 1% /tmp
/dev/dm-0 2048000 19784 2028216 1% /usr
/dev/dm-1 3096576 1758 3094818 1% /var
/dev/dm-2 13113840 5642 13108198 1% /home
So /var on server01 has 705.808 inodes, while server02 and server03 have 3.096.576 inodes on /var. But is this really the cause? As only 1% is used on each node.
If yes, how do I increase the inodes? (All filesystems are XFS out of / that is ext2)
/etc/fstab is the same on all 3 nodes. OS is Debian Lenny 64bit with Kernel 2.6.35.4.
Regards
I'm building a new database server and am trying to make sure I have the setup as correct as possible. The database storage is 22x 15.7k RPM Western Digital SAS drives in RAID10, in an external SAS enclosure with two RAID controllers. Initially, I created just a single volume on the SAS array, formatted with ext2. I calculated the Stride and Stripe-Width as follows:
- chunk_size = 128 Kb
- block_size = 4 Kb
- total_disks = 22
- data_disks = 11
- stride = chunk_size / block_size = 128 Kb / 4 Kb = 32 Kb
- stripe-width = stride * data_disks = 32 Kb * 11 = 352 Kb
I gave the Stride and Stripe-Width values to mkfs.ext2 when I created the filesystem.
I then tried another setup, which is where my question begins. I created two volumes on the SAS array, each with a different "primary" controller. When exported to the host, I used LVM2 to initialize them as Physical Volumes, created a Volume Group, and then passed '--stripes 2' to lvcreate in order to stripe the volumes. The purpose of this was to spread the IO load across both controllers, for hopefully higher performance.
There is a section in the "best practices" documentation for the SAS array that states, in reference to LUN segment (chunk) size:
When using a volume manager to collect multiple storage system LUNs into a Logical
Volume Manager (LVM) volume group (VG), the I/O stripe width is allocated across all of > the segments of all of the data drives in all of the LUNs. The adjusted formula becomes: LUN segment size = LVM I/O stripe width / (# of data drives/LUN * # of LUNs/VG)
Now, the Volume Group on the SAS array has 22 drives, 11 of which are data drives, and two LUNs. The Volume Group on the host has two physical volumes (the LUNs), and both LUNs access the same data drives. So given a LUN segment size of 128 Kb, would I calculate LVM I/O Stripe Width as
- 128 = LVM_Stripe_Width / (11 * 2)
- 128 * 22 = LVM_Stripe_Width
- 2816 = LVM_Stripe_Width
or
- 128 = LVM_Stripe_Width / (11 * 1)
- 128 * 11 = LVM_Stripe_Width
- 1408 = LVM_Stripe_Width
Then this leads me into the Stride and Stripe-width question for mkfs.ext2: Is it calculated the same way as in the initial setup, or is it different now because of the LVM layer? Would it become
- chunk_size = 128 Kb
- block_size = 4 Kb
- total_disks = 2
- data_disks = 2
- stride = chunk_size / block_size = 128 Kb / 4 Kb = 32 Kb
- stripe-width = stride * data_disks = 32 Kb * 2 = 64 Kb
where
- total_disks = 2
comes from the '--stripes 2' to lvcreate?
Thanks,
Kendall
I would like to mount an ext2/3 filesystem on a mac running 10.5.
I'm trying to install Linux on a single partition of a USB flash drive that's larger than 4gb.
The first place I went to is http://pendrivelinux.com. I can follow these instructions for installing Xubuntu 9.04 perfectly, which unfortunately break down when I try to scale it up beyond 4gb.
There are several other tools to do this (unetbootin and usb-creator) which follow a very similar formula.
I figured out that a big problem of mine was that all of these tools assume the USB drive is formatted in FAT32, which unfortunately cannot hold a single file larger than 4gb. This is unfortunate because I want to use just one partition, so that my persistance file, casper-rw, looks like one big partition to the OS once I've booted off of the USB drive.
I then tried following a myriad of instructions involving formatting the drive as one large ext2 filesystem and using extlinux to create a single bootable ext2 file system.
This doesn't work for me however, after about 20 attempts verifying and slightly tweaking the formula, I cannot seem to get a "good" bootable ext2 file system built. I'm not entirely sure what's going on, but it seems as though no matter how hard I try, I cannot get the ext2 file system to remain coherent after copying the Linux ISO contents over, copying the MBR, and executing extlinux to create the ext bootloader.
Every time, after I follow these steps (in any order) and reboot, I get an unbootable USB drive. If I then mount the drive under Linux again, I see a mess of a file system (inodes have clearly been screwed up somewhere along the way).
I suspected that the USB drive wasn't being fully flushed, so I tried using the "sync" and "unmount" commands before rebooting which didn't affect things at all.
I guess I have several possible questions - but let's start with the obvious - is there something I'm missing to create a bootable ext2 USB flash drive that's large (e.g. 16gb)?