Commands by mhs (29)

  • Monitor all DNS queries made by Firefox


    2
    NSPR_LOG_MODULES=nsHostResolver:5 NSPR_LOG_FILE=/tmp/log.txt firefox
    mhs · 2015-09-30 01:56:36 6
  • Monitor all DNS queries seen by the local machine


    1
    dnstop -l 3 enp1s0f0
    mhs · 2015-09-30 01:55:11 6
  • Convert SWF to video

    This will dump a raw BGRA pixel stream and WAV which must then be converted to video: ffmpeg -f rawvideo -c:v rawvideo -s 1280x720 -r 12 -pix_fmt bgra -i "${i%.*}".bgra -c:v libx264 -preset veryslow -qp 0 -movflags +faststart -i "${i%.*}".wav -c:a libfdk_aac -b:a 384k "${i%.*}".mp4 ; rm "${i%.*}".bgra "${i%.*}".wav Our example generates an x264/720p/12fps/AAC best-quality MP4. To get dump-gnash, first install the build-dependencies for gnash (this step is OS-specific). Then: git clone http://git.savannah.gnu.org/r/gnash.git ; cd gnash ; ./autogen.sh ; ./configure --enable-renderer=agg --enable-gui=dump --disable-menus --enable-media=ffmpeg --disable-jemalloc ; make


    0
    i=in.swf; dump-gnash -1 -j 1280 -k 720 -D "${i%.*}".bgra@12 -A "${i%.*}".wav "${i}"
    mhs · 2015-05-06 23:52:39 22
  • Find which fibre HBA a disk is connected to

    Useful for big systems with lots of cards. (Update: does not work with USB disks)


    0
    udevadm info -q all -n /dev/sdc | grep ID_PATH | cut -d'-' -f 2 | xargs -n 1 lspci -s
    mhs · 2015-01-27 15:34:02 6
  • Generate map of your hardware


    2
    lstopo -p -v --whole-system --whole-io output.svg
    mhs · 2015-01-27 15:16:54 6
  • Map the slot of an I/O card to its PCI bus address

    Recent hardware may or may not enumerate *both of* these values


    1
    dmidecode --type 9 |egrep 'Bus Address|Designation'
    mhs · 2015-01-27 15:13:59 5
  • Aptitude pattern match

    Could be dangerous, if you have many packages all beginning with 'foo' or 'bar'. This will easily remove them all from your system.


    1
    aptitude --purge remove ~i^foo ~i^bar
    mhs · 2015-01-27 15:00:48 9
  • Nice beep


    1
    xset b 50 1700 10
    mhs · 2015-01-27 14:38:58 5
  • Performance tip: compress /usr/

    Periodically run the one-liner above if/when there are significant changes to the files in /usr/ = Before rebooting, add following to /etc/fstab : = /squashed/usr/usr.sfs /squashed/usr/ro squashfs loop,ro 0 0 usr /usr aufs udba=reval,br:/squashed/usr/rw:/squashed/usr/ro 0 0 No need to delete original /usr/ ! (unless you don't care about recovery). Also AuFS does not work with XFS


    4
    [ ! -d /squashed/usr ] && mkdir -p /squashed/usr/{ro,rw} ; mksquashfs /usr /squashed/usr/usr.sfs.new -b 65536 ; mv /squashed/usr/usr.sfs.new /squashed/usr/usr.sfs ; reboot
    mhs · 2014-05-10 06:01:06 6
  • Increase SCT of external USB disk enclosure to one hour.

    So I had this 2TB Seagate external disk/USB enclosure which by default would spin-down its internal drive (it enters a standby mode) after four minutes of inactivity.. Spinning-up the inactive drive was an annoying delay when accessing files and also it severely interfered with NFS.. SCT stands for "Standby Condition Timer". To completely disable SCT: sdparm --clear STANDBY -6 /dev/sdb To return to original (default) SCT settings: sdparm -D -p 0x1a -6 /dev/sdb To verify the settings (before and after): sdparm -a /dev/sdb No need for vendor-provided MSWIN tools, etc.


    2
    sdparm -s SCT=36000 --save /dev/sdb
    mhs · 2013-04-19 13:26:18 3
  • Limit the cpu usage of a process

    Similar to `cpulimit`, although `prlimit` can be found shipped with recent util-linux. Example: limit CPU consumption to 10% for a math problem which ordinarily takes up 100% CPU: Before: bc -l <(echo "1234123412341234^12341234") See the difference `prlimit` makes: prlimit --cpu=10 bc -l <(echo "1234123412341234^12341234") To actually monitor the CPU usage, use `top`, `sar`, etc.. or: pidstat -C 'bc' -hur -p ALL 1


    4
    prlimit --cpu=10 sort -u hugefile
    mhs · 2013-02-27 15:59:11 5
  • Commandline document conversion with Libreoffice

    In this example, the docx gets converted to Open Document .odt format. For other formats, you'll need to specify the correct filter (Hint: see "Comments" link below for a nice list).


    15
    soffice --headless -convert-to odt:"writer8" somefile.docx
    mhs · 2012-12-27 15:08:38 6
  • Android PNG screenshot

    Works with *rooted* Android devices. 400x800 are the screen dimensions of a typical handheld smartphone.


    8
    adb pull /dev/graphics/fb0 /dev/stdout | ffmpeg -vframes 1 -vcodec rawvideo -f rawvideo -pix_fmt rgb32 -s 480x800 -i pipe:0 -f image2 -vcodec png screenshot.png
    mhs · 2012-12-26 13:21:18 18
  • Dump android contacts, sms

    Crude, but works. Note for security, /data/ will be inaccessible unless your device has been *rooted*. On the other hand, if a device has been rooted, its data is now wide open to anyone with a USB cable and the above "one-liner". `adb` is one of the platform tools in the android SDK. To get SMS messages: adb pull /data/data/com.android.providers.telephony/databases/mmssms.db ; sqlite3 -batch <<EOF contacts2.db <CR> .header on <CR> .mode tabs <CR> select * from sms; <CR> EOF


    2
    adb pull /data/data/com.android.providers.contacts/databases/contacts2.db ; sqlite3 -batch <<EOF contacts2.db <CR> .header on <CR> .mode tabs <CR> select * from data; <CR> EOF
    mhs · 2012-12-26 11:35:23 19
  • wget multiple files (or mirror) from NTLM-protected Sharepoint

    If you have to deal with MS Sharepoint which is (rarely, let's hope) used in e.g. certain corporate environments). This uses Cntlm. For single files, just use cURL -- its NTLM authentication works quite well. # /etc/cntlm.conf: # Username account # Domain domain # Password ############ # Proxy 10.20.30.40 (IP of the sharepoint site) # NoProxy * # Listen 3128


    1
    http_proxy=http://127.0.0.1:3128 wget --http-user='domain\account' --http-password='###' -p -r -l 8 --no-remove-listing -P . 'http://sp.corp.com/teams/Team/Shared%20Documents/Forms/AllItems.aspx?RootFolder=%2fteams%2fTeam%2fShared%20Documents%2fFolder'
    mhs · 2012-12-26 09:03:55 2
  • Serial console to a Vmware VM

    Create a serial console with "socket (named pipe)" of "/tmp/socket", "from:server, to:virtual machine" in vmware player, etc.. gui. Run the above command after you have booted the guest OS (which should also be configured for serial console).


    1
    socat unix-connect:/tmp/socket stdio,echo=0,raw
    mhs · 2012-12-19 07:58:09 6
  • parted - scripted partitioning (of all multipathed SAN LUNs)

    `multipath -ll` requires Device Mapper multipath.conf configuration. And of course, replace "3PARdata,VV" with your disk array's SCSI vendor,LUN name. - GPT partition table allows you to create >2TB partitions


    1
    for i in $(multipath -ll | grep "3PARdata,VV"|awk '{print $1}') ; do parted -a optimal /dev/mapper/$i --script -- mklabel gpt mkpart primary 1 -1 set 1 lvm on ; done
    mhs · 2012-09-12 15:30:36 5
  • Formatted list - WWNs of all LUNs

    Use `scsi_id` to positively identify which LUNs are which (i.e. compare with the list of LUNs you created on your disk array) (shown: RHEL5 usage) Debian usage: # for i in /dev/sd* ; do wwn=`/lib/udev/scsi_id -g --device $i` ; [ "$wwn" != "" ] && echo -e ${i##*/}'\t'$wwn ;done Show Sample Output


    1
    for i in /sys/block/sd* ; do wwn=`/lib/udev/scsi_id -g -s /block/${i##*/}` ; [ "$wwn" != "" ] && echo -e ${i##*/}'\t'$wwn ;done
    mhs · 2012-09-12 14:14:53 2
  • detect partitions

    `blkid` is an interface to libuuid - it can read Device Mapper, EVMS, LVM, MD, and regular block devices. -c /dev/null - Do not use cached output from /etc/blkid.tab or /etc/blkid/blkid.tab (RHEL) -i - Display I/O Limits (aka I/O topology) information (not available in RHEL) -p - Low-level superblock probing mode (not available in RHEL) Show Sample Output


    2
    blkid -c /dev/null
    mhs · 2012-09-12 13:34:41 4
  • Keep a copy of the raw Youtube FLV,MP4,etc stored in /tmp/

    Certain Flash video players (e.g. Youtube) write their video streams to disk in /tmp/ , but the files are unlinked. i.e. the player creates the file and then immediately deletes the filename (unlinking files in this way makes it hard to find them, and/or ensures their cleanup if the browser or plugin should crash etc.) But as long as the flash plugin's process runs, a file descriptor remains in its /proc/ hierarchy, from which we (and the player) still have access to the file. The method above worked nicely for me when I had 50 tabs open with Youtube videos and didn't want to have to re-download them all with some tool.


    8
    lsof -n -P|grep FlashXX|awk '{ print "/proc/" $2 "/fd/" substr($4, 1, length($4)-1) }'|while read f;do newname=$(exiftool -FileModifyDate -FileType -t -d %Y%m%d%H%M%S $f|cut -f2|tr '\n' '.'|sed 's/\.$//');echo "$f -> $newname";cp $f ~/Vids/$newname;done
    mhs · 2012-02-25 01:49:45 3
  • Hide the name of a process listed in the `ps` output

    exec -a $NAME $COMMAND $ARGS `your_cmd -erase_all_files` is the real process, but harmless-looking getty appears in the process table. Never actually had a need to do this, but interesting nonetheless... Tested in bash, dash. -a $NAME "pass NAME as the zeroth argument to COMMAND", i.e. customise the name of the process (as commonly seen with `ps`) Show Sample Output


    16
    exec -a "/sbin/getty 38400 tty7" your_cmd -erase_all_files
    mhs · 2012-02-01 10:54:03 6
  • Show 'Hardware path'-style tree of all devices in Linux

    Show Sample Output


    6
    lshw -short
    mhs · 2011-06-28 23:32:30 6
  • Find out the starting directory of a script

    Invoked from within a shell script, this will print the directory in which the script resides. Doesn't depend on external tools, /proc/self/*, etc.. (`echo` is a shell builtin.) To see the *current working* directory of a script, use `pwd`.


    13
    echo "${0%/*}"
    mhs · 2011-04-17 12:09:56 10
  • move messages directly from one IMAP inbox to another

    This one-liner was useful in helping someone I know to get off of MS Exchange. `mailutil` proved to be a much better alternative than `fetchmail` or `getmail` in this case. It quickly moved all mails to the destination server (a simple Dovecot/Maildir setup), with no need to convert back and forth between mbox/maildir on the user's own system.


    2
    mailutil appenddelete '{src.mailsrv1.com:993/imap/norsh/notls/ssl/novalidate-cert/user="username"}INBOX' '{dest.mailsrv2.com:143/imap/norsh/notls/user="username"}INBOX'
    mhs · 2011-02-08 09:37:05 2
  • Stop Flash from tracking everything you do.

    Brute force way to block all LSO cookies on a Linux system with the non-free Flash browser plugin. Works just fine for my needs. Enjoy. Show Sample Output


    18
    for i in ~/.adobe ~/.macromedia ; do ( rm $i/ -rf ; ln -s /dev/null $i ) ; done
    mhs · 2010-12-29 13:23:48 10
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List the libraries used by an application
For example, you need to make a copy of all the libraries that a certain application uses, with this command you can list and copy them.

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

Perpetual calendar
Gets any date since today. Other examples of recognized expressions are "2 years 4 days ago", "7 months" (in the future), "next Sunday", "yesterday", "tomorrow", etc.

find duplicate processes
This command will allow to search for duplicate processes and sort them by their run count. Note that if there are same processes run by different users you'll see only one user in the result line, so you'll need to do: $ ps aux | grep to see all users that run this command.

list files recursively by size

Print trending topics on Twitter

ARP Scan
A much quicker and (not dirtier) option. use the man page for help. On linux/ubuntu you will need to `sudo apt-get -y install arp-scan`.

Print current running shell, PID
works as well as echo $0, but also prints process id, which pts you're using. echo $SHELL doesn't always get updated when changing shells, so this is a better solution than that. Just one more variation on a theme.

Grab the first 3 octets of your ip addresses
For machines that have many ip blocks spanning different Class C's, this will show which ones.

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

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