Commands by lig0n (2)

  • Scrap everything and use `gawk` to do all the magic, since it's like the future or something. gawk 'match($11, /[a-z]{3}$/) && match($9, /^ata-/) { gsub("../", ""); print $11,"\t",$9 }' Yank out only ata- lines that have a drive letter (ignore lines with partitions). Then strip ../../ and print the output. Yay awk. Be sure to see the alternatives as my initial command is listed there. This one is a revision of the original. Show Sample Output


    2
    ls -l /dev/disk/by-id |gawk 'match($11, /[a-z]{3}$/) && match($9, /^ata-/) { gsub("../", ""); print $11,"\t",$9 }' |sort
    lig0n · 2015-05-18 15:42:33 6
  • This is much easier to parse and do something else with (eg: automagically create ZFS vols) than anything else I've found. It also helps me keep track of which disks are which, for example, when I want to replace a disk, or image headers in different scenarios. Being able to match a disk to the kernels mapping of said drive the disks serial number is very helpful ls -l /dev/disk/by-id Normal `ls` command to list contents of /dev/disk/by-id grep -v "wwn-" Perform an inverse search - that is, only output non-matches to the pattern 'wwn-' egrep "[a-zA-Z]{3}$" A regex grep, looking for three letters and the end of a line (to filter out fluff) sed 's/\.\.\/\.\.\///' Utilize sed (stream editor) to remove all occurrences of "../../" sed -E 's/.*[0-9]{2}:[0-9]{2}\s//' Strip out all user and permission fluff. The -E option lets us use extended (modern) regex notation (larger control set) sed -E 's/->\ //' Strip out ascii arrows "-> " sort -k2 Sort the resulting information alphabetically, on column 2 (the disk letters) awk '{print $2,$1}' Swap the order of the columns so it's easier to read/utilize output from sed 's/\s/\t/' Replace the space between the two columns with a tab character, making the output more friendly For large ZFS pools, this made creating my vdevs immeasurably easy. By keeping track of which disks were in which slot (spreadsheet) via their serial numbers, I was able to then create my vols simply by copying and pasting the full output of the disk (not the letter) and pasting it into my command. Thereby allowing me to know exactly which disk, in which slot, was going into the vdev. Example command below. zpool create tank raidz2 -o ashift=12 ata-... ata-... ata-... ata-... ata-... ata-... Show Sample Output


    0
    ls -l /dev/disk/by-id |grep -v "wwn-" |egrep "[a-zA-Z]{3}$" |sed 's/\.\.\/\.\.\///' |sed -E 's/.*[0-9]{2}:[0-9]{2}\s//' |sed -E 's/->\ //' |sort -k2 |awk '{print $2,$1}' |sed 's/\s/\t/'
    lig0n · 2015-01-25 19:29:40 5

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