Commands by alf (5)

  • Untar a directory in a tar file over ssh

    This may be listed already but this command is useful to untar a specific directory to a different server.


    0
    cat tarfile.tar.gz | ssh server.com " cd /tmp; tar xvzf - directory/i/want"
    alf · 2011-02-11 17:10:01 1
  • Automatd ssh public key setup without ssh-copy-id

    Some servers don't have ssh-copy-id, this works in those cases. It will ask for the destination server, this can be IP, hostname, or user@hostname if different from current user. Ssh keygen will let you know if a pubkey already exists on your system and you can opt to not overwrite it.


    -2
    echo 'Host or User@Host?:'; read newserver && ssh-keygen -N "" -t rsa -f ~/.ssh/id_rsa ; ssh $newserver cat <~/.ssh/id_rsa.pub ">>" ~/.ssh/authorized_keys ; ssh $newserver
    alf · 2010-05-07 06:24:53 1
  • Show interface/ip using awk

    Interfaces like lo can be omitted from the beginning, there are probably better ways of doing this, i'm a noob at awk. Show Sample Output


    5
    ifconfig -a| awk '/^wlan|^eth|^lo/ {;a=$1;FS=":"; nextline=NR+1; next}{ if (NR==nextline) { split($2,b," ")}{ if ($2 ~ /[0-9]\./) {print a,b[1]}; FS=" "}}'
    alf · 2010-04-15 04:34:28 3
  • Update zone file Serial numbers

    Will edit *.db files in the same directory with todays date. Useful for doing a mass update to domains on a nameserver, adding spf records, etc. Looks for a string starting with 200 or 201 followed by 7 numbers, and replaces with todays date. This won't overwrite Ip's but i would still do some double checking after running this. Make sure your server's date is correct, otherwise insert your own serial number. rndc reload should usually follow this command.


    7
    sed -i 's/20[0-1][0-9]\{7\}/'`date +%Y%m%d%I`'/g' *.db
    alf · 2010-03-24 07:28:58 3
  • Use ping to test if a server is up

    Bash scrip to test if a server is up, you can use this before wget'ing a file to make sure a blank one isn't downloaded.


    -1
    if [ "$(ping -q -c1 google.com)" ];then wget -mnd -q http://www.google.com/intl/en_ALL/images/logo.gif ;fi
    alf · 2010-03-23 04:15:03 7

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Show changed files, ignoring permission, date and whitespace changes
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Find recursively, from current directory down, files and directories whose names contain single or multiple whitespaces and replace each such occurrence with a single underscore.
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One-liner to generate Self-Signed SSL Certificate+Key without any annoying prompts or CSRs
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change directory to actual path instead of symlink path
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