<div dir="ltr">Hi,<br>Yesterday my harddrive had an inconvenient event: when I was using a d-i from testing I accidentally overwritten on of the pv's connected to the lvm.<br>I started to panic and found myself making more damage by running <span dir="ltr">vgreduce --<em>remove</em>-<em>missing</em></span> since in one of the rescue files it noted this is the way to fix it.<br>
<br>the config was : <br><br>/dev/sda7 pv0<br>/dev/sda8 pv1<br><br>digging in the parrtion i found the lvm declaration : <br><br>00000200 4c 41 42 45 4c 4f 4e 45 01 00 00 00 00 00 00 00 |LABELONE........|<br>00000210 e1 4c e7 48 20 00 00 00 4c 56 4d 32 20 30 30 31 |.L.H ...LVM2 001|<br>
00000220 47 42 73 58 46 51 52 64 58 53 69 4d 68 70 50 68 |GBsXFQRdXSiMhpPh|<br>00000230 6c 65 69 71 66 4d 35 35 37 31 61 4a 67 51 41 61 |leiqfM5571aJgQAa|<br>00000240 00 8c 71 7c 07 00 00 00 00 00 03 00 00 00 00 00 |..q|............|<br>
00000250 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................|<br>00000260 00 00 00 00 00 00 00 00 00 10 00 00 00 00 00 00 |................|<br>00000270 00 f0 02 00 00 00 00 00 00 00 00 00 00 00 00 00 |................|<br>
00000280 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................|<br><br>digging in the raw data of the /dev/sda7 (I think) I found(*) the filesystems that were on the lvm : <br><br>0002fff0 b8 ff 74 b8 ff 74 b8 ff 74 b8 ff 74 b8 ff 74 b8 |..t..t..t..t..t.|<br>
00030000 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................|<br>*<br>00030400 00 20 25 00 00 70 94 00 00 6c 07 00 13 13 4e 00 |. %..p...l....N.|<br>00030410 01 f0 24 00 00 00 00 00 02 00 00 00 02 00 00 00 |..$.............|<br>
00030420 00 80 00 00 00 80 00 00 00 20 00 00 05 dc b0 4c |......... .....L|<br>00030430 c4 df b0 4c a2 01 25 00 53 ef 01 00 01 00 00 00 |...L..%.S.......|<br>00030440 ae b0 f2 4a 00 4e ed 00 00 00 00 00 01 00 00 00 |...J.N..........|<br>
00030450 00 00 00 00 0b 00 00 00 00 01 00 00 3c 00 00 00 |............<...|<br>00030460 02 00 00 00 03 00 00 00 6f c8 71 b2 99 4e 4c 1f |........o.q..NL.|<br>00030470 85 25 3e e9 9a 2c 55 45 00 00 00 00 00 00 00 00 |.%>..,UE........|<br>
00030480 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................|<br><br>knowing the sizes I dd data (this is from memory) - I think the partition startes 30000 hence 3*16^4 / 1024 = 192 <br><br>dd if=/dev/sda7 of=filename bs=1024 count=16M seek=192<br>
tried to mount but without success.<br><br><br>(1) - hd /dev/sda7 | less found what i think is the superblock : <br><br><br>I found that during the tut I run the hence getting a backup of some of the data (from backup/fileserver)<br>
<br># Generated by LVM2 version 2.02.66(2) (2010-05-20): Sun Oct 10 01:09:27 2010<br><br>contents = "Text Format Volume Group"<br>version = 1<br><br>description = "Created *after* executing 'vgcfgbackup'"<br>
<br>creation_host = "midgard" # Linux midgard 2.6.32-5-amd64 #1 SMP Thu Aug 12 13:01:50 UTC 2010 x86_64<br>creation_time = 1286665767 # Sun Oct 10 01:09:27 2010<br><br>fileserver {<br> id = "YKE4Rs-gcaS-oWuy-8dVG-0Loq-MrsL-8m7K8v"<br>
seqno = 11<br> status = ["RESIZEABLE", "READ", "WRITE"]<br> flags = []<br> extent_size = 8192 # 4 Megabytes<br> max_lv = 0<br> max_pv = 0<br>
<br> physical_volumes {<br><br> pv0 {<br> id = "GBsXFQ-RdXS-iMhp-Phle-iqfM-5571-aJgQAa"<br> device = "/dev/sda7" # Hint only<br><br>
status = ["ALLOCATABLE"]<br> flags = []<br> dev_size = 62798022 # 29.9444 Gigabytes<br> pe_start = 384<br> pe_count = 7665 # 29.9414 Gigabytes<br>
}<br><br> pv1 {<br> id = "fVkJmY-pdwD-bub8-URE8-lNc2-eyhr-IIxIez"<br> device = "unknown device" # Hint only<br><br> status = ["ALLOCATABLE"]<br>
flags = ["MISSING"]<br> dev_size = 79409232 # 37.8653 Gigabytes<br> pe_start = 384<br> pe_count = 9693 # 37.8633 Gigabytes<br>
}<br> }<br><br> logical_volumes {<br><br> video {<br> id = "wuLloD-3u0J-YHeu-Glxk-fsbC-tOyp-RbGBws"<br> status = ["READ", "WRITE", "VISIBLE"]<br>
flags = []<br> segment_count = 2<br><br> segment1 {<br> start_extent = 0<br> extent_count = 7665 # 29.9414 Gigabytes<br>
<br> type = "striped"<br> stripe_count = 1 # linear<br><br> stripes = [<br> "pv0", 0<br>
]<br> }<br> segment2 {<br> start_extent = 7665<br> extent_count = 2063 # 8.05859 Gigabytes<br>
<br> type = "striped"<br> stripe_count = 1 # linear<br><br> stripes = [<br> "pv1", 0<br>
]<br> }<br> }<br><br> audio {<br> id = "a1U4E0-7c1G-TqLc-p7H0-ZcQc-QMZI-1znD0K"<br> status = ["READ", "WRITE", "VISIBLE"]<br>
flags = []<br> segment_count = 2<br><br> segment1 {<br> start_extent = 0<br> extent_count = 2560 # 10 Gigabytes<br>
<br> type = "striped"<br> stripe_count = 1 # linear<br><br> stripes = [<br> "pv1", 5135<br>
]<br> }<br> segment2 {<br> start_extent = 2560<br> extent_count = 768 # 3 Gigabytes<br>
<br> type = "striped"<br> stripe_count = 1 # linear<br><br> stripes = [<br> "pv1", 4161<br>
]<br> }<br> }<br><br> opt {<br> id = "npePvz-nfHw-ILxe-K1oX-bmxa-HTfn-wfkRi2"<br> status = ["READ", "WRITE", "VISIBLE"]<br>
flags = []<br> segment_count = 2<br><br> segment1 {<br> start_extent = 0<br> extent_count = 1998 # 7.80469 Gigabytes<br>
<br> type = "striped"<br> stripe_count = 1 # linear<br><br> stripes = [<br> "pv1", 7695<br>
]<br> }<br> segment2 {<br> start_extent = 1998<br> extent_count = 2098 # 8.19531 Gigabytes<br>
<br> type = "striped"<br> stripe_count = 1 # linear<br><br> stripes = [<br> "pv1", 2063<br>
]<br> }<br> }<br> }<br>}<br><br><br>tried doing : .<br><br> vgcfgrestore -f fileserver fileserver<br> Couldn't find device with uuid fVkJmY-pdwD-bub8-URE8-lNc2-eyhr-IIxIez.<br>
Cannot restore Volume Group fileserver with 1 PVs marked as missing.<br> Restore failed.<br> <br>
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