From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx1.redhat.com (mx1.redhat.com [172.16.48.31]) by int-mx1.corp.redhat.com (8.13.1/8.13.1) with ESMTP id l22BhsWL029190 for ; Fri, 2 Mar 2007 06:43:54 -0500 Received: from mail2.syneticon.net (mail.syneticon.net [213.239.212.131]) by mx1.redhat.com (8.13.1/8.13.1) with ESMTP id l22BhpOw028589 for ; Fri, 2 Mar 2007 06:43:51 -0500 Received: from localhost (localhost [127.0.0.1]) by mail2.syneticon.net (Postfix) with ESMTP id B81BC545D5 for ; Fri, 2 Mar 2007 12:43:35 +0100 (CET) Received: from mail2.syneticon.net ([127.0.0.1]) by localhost (linux [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 27236-14 for ; Fri, 2 Mar 2007 12:42:25 +0100 (CET) Received: from postfix1.syneticon.net (postfix1.syneticon.net [192.168.112.6]) by mail2.syneticon.net (Postfix) with ESMTP for ; Fri, 2 Mar 2007 12:42:25 +0100 (CET) Received: from localhost (filter1.syneticon.net [192.168.113.3]) by postfix1.syneticon.net (Postfix) with ESMTP id 95291946C for ; Fri, 2 Mar 2007 12:42:22 +0100 (CET) Received: from postfix1.syneticon.net ([192.168.113.4]) by localhost (mx03.syneticon.net [192.168.113.3]) (amavisd-new, port 10025) with ESMTP id aCo3GEdZyhwL for ; Fri, 2 Mar 2007 12:41:21 +0100 (CET) Received: from [81.173.142.58] (xdsl-81-173-142-58.netcologne.de [81.173.142.58]) by postfix1.syneticon.net (Postfix) with ESMTP for ; Fri, 2 Mar 2007 12:42:19 +0100 (CET) Message-ID: <45E80D9A.6050409@wpkg.org> Date: Fri, 02 Mar 2007 12:42:18 +0100 From: Tomasz Chmielewski MIME-Version: 1.0 Subject: Re: [linux-lvm] moving logical volumes to another system *remotely* - how? References: <45DED477.8040809@wpkg.org> <20070223124452.GB22388@homer.panici.net> <45DF0F5B.6000506@wpkg.org> <20070223173220.GD9124@soda.linbit> In-Reply-To: <20070223173220.GD9124@soda.linbit> Content-Transfer-Encoding: 7bit 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: Content-Type: text/plain; charset="us-ascii"; format="flowed" To: LVM general discussion and development Lars Ellenberg schrieb: > / 2007-02-23 16:59:23 +0100 > \ Tomasz Chmielewski: >> paddy@panici.net schrieb: >>> On Fri, Feb 23, 2007 at 12:48:07PM +0100, Tomasz Chmielewski wrote: >>>> I have a server which stores several LVM-2 logical volumes. >>>> >>>> As this system is pretty loaded, I'd like to move some of the logical >>>> volumes to another machine. It has to be done remotely, so I can't do it >>>> as described in the LVM HOWTO (where one basically adds/replaces disks in one machine). >>>> >>>> My common sense tells me that I should: >>>> >>>> 1. Unmount/not use the logical volumes on the source server >>>> 2. Make volumes of the same size on the target server >>>> 3. Copy it somehow over network >>>> >>>> >>>> I'm not sure of 2 (make volumes of exactly the same size) >>> check your PE size, otherwise does what it says on the tin. >> Hmm, how? I just want to move some (not all) logical volumes. >> >> I guess fdisk is a good idea? >> >> # fdisk -l /dev/LVM2/ocsi1 >> >> Disk /dev/LVM2/ocsi1: 3221 MB, 3221225472 bytes >> >> >> 3221225472 / 1024 = 3145728 >> >> >> lvcreate -L3145728k -n ocsi1 LVM2 >> >> Hmm, hopefully, it's the right size? > > > how about: > lvs --units k Indeed this one is more LVM-specific. Didn't work for me though - my kernel oopsed a while ago, and all lvm commands stopped to work. When started, they were just in a "D" state. The kernel oopsed after I created a snapshot, made it full (invalidated), and tried to remove it. The kernel I used was 2.6.17.8 running on Debian-ARM: # lvremove /dev/LVM2/pdc-backup-new /dev/sda2: Checksum error Do you really want to remove active logical volume "pdc-backup-new"? [y/n]: y Segmentation fault # dmesg Unable to handle kernel paging request at virtual address 31376632 pgd = 8cce8000 [31376632] *pgd=00000000 Internal error: Oops: f3 [#1] Modules linked in: iscsi_trgt bonding dm_snapshot dm_mirror loop CPU: 0 PC is at exit_exception_table+0x44/0x70 [dm_snapshot] LR is at exit_exception_table+0x40/0x70 [dm_snapshot] pc : [<7f00bbe4>] lr : [<7f00bbe0>] Not tainted sp : 8718dd24 ip : 31376632 fp : 8718dd48 r10: 804f14e0 r9 : 8718c000 r8 : 00000080 r7 : 90ba4218 r6 : 00000043 r5 : 8ee3577c r4 : 31376632 r3 : 8e6e7000 r2 : 00000078 r1 : 8e6e7000 r0 : 804f14e0 Flags: Nzcv IRQs on FIQs on Mode SVC_32 Segment user Control: 397F Table: ACCE8000 DAC: 00000015 Process lvremove (pid: 17844, stack limit = 0x8718c198) Stack: (0x8718dd24 to 0x8718e000) dd20: 8ee35740 8f643940 8f643944 90b9f020 00200200 00100100 8718dd70 dd40: 8718dd4c 7f00bcb0 7f00bbac 90b9f020 8abc4460 00000001 00000034 00000004 dd60: c134fd04 8718dd90 8718dd74 8016791c 7f00bc1c 8ee355c0 8abc4460 00000000 dd80: 8016aab0 8718ddac 8718dd94 80166888 801678a8 8cf55aa0 8abc4460 8718c000 dda0: 8718ddc4 8718ddb0 8016a284 80166828 90b98000 90b98000 8718ddd8 8718ddc8 ddc0: 8016aaf4 8016a208 000ae5d8 8718df44 8718dddc 8016a888 8016aabc 8be31468 dde0: 00000000 8718de00 8718ddf4 00000004 00000006 00000000 00004000 00000134 de00: 00000000 00000000 0000020c 00000000 00000000 0000fd26 00000000 00000000 de20: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 de40: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 de60: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 de80: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 dea0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 dec0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 dee0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 df00: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 df20: 8619d0a0 000ae5d8 c134fd04 00000005 8001fea4 2aadea7c 8718df5c 8718df48 df40: 800826a8 8016a5ac 8619d0a0 000ae5d8 8718df84 8718df60 80082920 8008264c df60: ffffffff 8718dfac 8619d0a0 fffffff7 c134fd04 00000036 8718dfa4 8718df88 df80: 80082990 800826c4 00000000 0004537c 2aad66d0 2aad5274 00000000 8718dfa8 dfa0: 8001fd00 8008295c 0004537c 2aad66d0 00000005 c134fd04 000ae5d8 00001220 dfc0: 0004537c 2aad66d0 2aad5274 000b8808 0000004e 2aad66cc 2aadea7c 000ae5d8 dfe0: 2aadebec 7e987c3c 2aad44f8 2ac811e4 80000010 00000005 b7118d2a f2641dfd Backtrace: [<7f00bba0>] (exit_exception_table+0x0/0x70 [dm_snapshot]) from [<7f00bcb0>] (snapshot_dtr+0xa0/0xf4 [dm_snapshot]) [<7f00bc10>] (snapshot_dtr+0x0/0xf4 [dm_snapshot]) from [<8016791c>] (dm_table_put+0x80/0xe4) [<8016789c>] (dm_table_put+0x0/0xe4) from [<80166888>] (dm_put+0x6c/0xcc) r7 = 8016AAB0 r6 = 00000000 r5 = 8ABC4460 r4 = 8EE355C0 [<8016681c>] (dm_put+0x0/0xcc) from [<8016a284>] (__hash_remove+0x88/0x9c) r6 = 8718C000 r5 = 8ABC4460 r4 = 8CF55AA0 [<8016a1fc>] (__hash_remove+0x0/0x9c) from [<8016aaf4>] (dev_remove+0x44/0x64) r5 = 90B98000 r4 = 90B98000 [<8016aab0>] (dev_remove+0x0/0x64) from [<8016a888>] (ctl_ioctl+0x2e8/0x3a8) r4 = 000AE5D8 [<8016a5a0>] (ctl_ioctl+0x0/0x3a8) from [<800826a8>] (do_ioctl+0x68/0x78) [<80082640>] (do_ioctl+0x0/0x78) from [<80082920>] (vfs_ioctl+0x268/0x298) r5 = 000AE5D8 r4 = 8619D0A0 [<800826b8>] (vfs_ioctl+0x0/0x298) from [<80082990>] (sys_ioctl+0x40/0x60) r7 = 00000036 r6 = C134FD04 r5 = FFFFFFF7 r4 = 8619D0A0 [<80082950>] (sys_ioctl+0x0/0x60) from [<8001fd00>] (ret_fast_syscall+0x0/0x2c) r6 = 2AAD5274 r5 = 2AAD66D0 r4 = 0004537C Code: e59c4000 ea000002 eb418145 e1a0c004 (e5944000) So fdisk was the only way to read these partitions size - well, I also did "dd if=partition of=/dev/null" to measure the size :) >>>> and 3 (how to copy it all over network, if possible, using SSH only). >>> netcat and dd over forwarded port >> Thanks for the idea. > > dd if=/dev/$vg/$lv bs=32M | > buffer -S 10m -s 512k | > gzip -1 | > ssh -T $target -- \ > "gunzip | > buffer -s 512k | > dd bs=32M of=/dev/$t_vg/$t_lv" > I found netcat extremely slow (only 0.5-1 MB/s), perhaps same would be with SSH. As I use iSCSI, I used such approach: 600 MHz ARM SAN <-iSCSI-> server <-iSCSI> 600 MHz Pentium mobile SAN On "server" I just used: dd if=iSCSI-ARM/part of=iSCSI-Pentium/part With source/destination being the same size. It was way faster, 6-8 MB/s (I had lots of gigabytes to copy). Normal transfer rates between SAN server are about 20-40 MB/s; perhaps it was that slow also because of an earlier kernel oops and a couple of lvm processes in "D" state. -- Tomasz Chmielewski http://wpkg.org