Commands tagged kernel (37)

  • after kernel build with make deb-pkg, I like to install the 4 newest packages that exist in the directory. Beware: might be fewer for you....

    sudo dpkg -i `ls -tr *.deb | tail -n4`
    _john · 2011-10-09 14:20:11 4
  • Gets the (previously obtainable with: finger ) info of the latest linux kernel versions available. Show Sample Output

    curl ''
    Testuser_01 · 2012-03-04 21:10:19 5
  • Well, this is quite useful for testing if your hardware watchdog is working properly.

    echo c > /proc/sysrq-trigger
    fangfufu · 2013-05-07 19:41:40 6
  • echo 1 > /proc/sys/sunrpc/nfs_debug && tail -f /var/log/messages to debug NFS issues.

    echo 1 > /proc/sys/sunrpc/nfs_debug
    harpo · 2014-08-12 14:40:55 9
  • Get newest kernel version by parsing the most bleeding-edge Makefile possible. Useful for doing things like writing live ebuilds and/or self-updating PKGBUILDs for testing purposes. Breakdown: * wget -qO - — retrieve Makefile and pipe to stdout * head -n5 — only the first 5 lines are relevant, that's where all the version variables are grep -E '\ \=\ [0-9]{1,}' — version variables always have an equals sign followed by a number * cut -d' ' -f3 — extract the individual numbers from the version variables * tr '\n' '.' — replace newlines with periods * sed -e "s/\.$// — remove trailing period Show Sample Output

    wget -qO - | head -n5 | grep -E '\ \=\ [0-9]{1,}' | cut -d' ' -f3 | tr '\n' '.' | sed -e "s/\.$//"
    realkstrawn93 · 2021-04-27 17:12:05 436
  • Kernel developers might need to know what indices to map to the IOAPIC if building a new kernel from scratch. This command gives users a guide to go off of.

    cp /proc/interrupts irq-ref.txt
    realkstrawn93 · 2022-02-23 19:53:02 540
  • Whenever you compile a new kernel, there are always new modules. The best way to make sure you have the correct modules loaded when you boot is to add all your modules in the modules.autoload file (they will be commented) and uncomment all those modules you need. Also a good way to keep track of the available modules in your system. For other distros you may have to change the name of the file to /etc/modprobe.conf Show Sample Output

    find /lib/modules/`uname -r`/ -type f -iname '*.o' -or -iname '*.ko' |grep -i -o '[a-z0-9]*[-|_]*[0-9a-z]*\.ko$' |xargs -I {} echo '# {}' >>/etc/modules.autoload.d/kernel-2.6
    paragao · 2010-01-13 02:12:08 5
  • Disable randomisation address Show Sample Output

    echo 0 > /proc/sys/kernel/randomize_va_space
    gunslinger_ · 2010-07-11 16:42:42 4
  • Same as 7272 but that one was too dangerous so i added -P to prompt users to continue or cancel Note the double space: "...^ii␣␣linux-image-2..." Like 5813, but fixes two bugs: [1]This leaves the meta-packages 'linux-headers-generic' and 'linux-image-generic' alone so that automatic upgrades work correctly in the future. [2]Kernels newer than the currently running one are left alone (this can happen if you didn't reboot after installing a new kernel).

    sudo aptitude remove -P $(dpkg -l|awk '/^ii linux-image-2/{print $2}'|sed 's/linux-image-//'|awk -v v=`uname -r` 'v>$0'|sed 's/-generic//'|awk '{printf("linux-headers-%s\nlinux-headers-%s-generic\nlinux-image-%s-generic\n",$0,$0,$0)}')
    Bonster · 2011-04-25 05:19:57 4
  • Fetches latest stable release version from first entry between tags Show Sample Output

    curl -s -k | sed -n -e 's@.*<guid>\(.*\)</guid>.*@\1@p' | grep 'stable' | head -1 | awk -F , '{print $3}'
    Wafelijzer · 2013-12-17 23:59:27 7

  • -4
    aptitude purge linux-image | grep ^i | grep -v $(uname -r)
    lgallardo · 2010-06-11 22:20:42 6
  • Display the machine "hardware name" 32 or 64 bit. "x86_64" is shown on 64 bit machines "i686" is typically shown on 32 bit machines (although, you might also see "i386" or "i586" on older Linuxen). On other "unix-like" systems, other hardware names will be displayed. For example, on AIX, "uname -m" gives the "machine sequence number". For whatever reason, IBM decided that "uname -M" would give the machine type and model. (ref: ) On Sun Solaris, "uname -m" can be used to determine the chip type and "isainfo -v" will reveal if the kernel is 64 or 32 bit. (ref: ) A more reliable way to determine "64-bit ness" across different Unix type systems is to compile the following simple C program: cat <<eeooff > bits.c /* * program bits.c * purpose Display "32" or "64" according to machine type * written January 2013 * reference */ /* hmm, curious that angle-brackets removed by data input processing? */ #include "/usr/include/stdio.h" long lv = 0xFFFFFFFF; main ( ) { printf("%2d\n",(lv < 0)?32:64); } eeooff Compile and run thusly: cc -o bits bits.c; ./bits Show Sample Output

    uname -m # display machine "hardware name"
    mpb · 2013-01-04 11:46:43 16
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