Tips, Tricks, and Info!
Lennart Andersen Linux Debian Suse Networking OSX Windows Links Top Virus / Security Issues

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#Linux   Top
BASH HOTKEYS
  • Ctrl-a - Move to the start of the line.
  • Ctrl-e - Move to the end of the line.
  • Ctrl-b - Move back one character.
  • Alt-b - Move back one word.
  • Ctrl-f - Move forward one character.
  • Alt-f - Move forward one word.
  • Alt-] x - Where x is any character, moves the cursor forward to the next occurrence of x.
  • Alt-Ctrl-] x - Where x is any character, moves the cursor backwards to the previous occurrence of x.
  • Ctrl-u - Delete from the cursor to the beginning of the line.
  • Ctrl-k - Delete from the cursor to the end of the line.
  • Ctrl-w - Delete from the cursor to the start of the word.
  • Esc-Del - Delete previous word (may not work, instead try Esc followed by Backspace)
  • Ctrl-y - Pastes text from the clipboard.
  • Ctrl-l - Clear the screen leaving the current line at the top of the screen.
  • Alt-r - Undo all changes to the line.
    		•
    My favourite common alias links
  • alias ll='ls -l'
  • alias la='ls -A'
  • alias l='ls -lA'
  • alias mutt="mutt -y"
  • alias gf="find . -type f -print0 | xargs -0 -e grep -n -e"
  • alias gf-color="find . -type f -print0 | xargs -0 grep -i -n -I --max-count=50 --color=always"
  • alias xtop="xterm -e top"
  • alias clr='clear;echo "Currently logged in on$(tty), as $(whoami) in directory $(pwd)."'
  • alias tgz='tar -cvvzf'
  • alias tbz2='tar -cvvjf'
  • alias utgz='tar -xvvzf'
  • alias utbz2='tar -xvvjf'
  • alias mktar='tar -cvvf'
  • alias untar='tar -xvvf'
  • alias nano='nano -w'
  • alias df='df -h'
  • alias vi="vim"
  • alias server_name="ssh -l user ipaddress"
  • alias findbigfiles="find . -type f -exce ls -s {} \; | sort -n -r | head -5"
  • alias psf="ps -e f"
    		•
    find biggest subdirect. du -kx | egrep -v "\./.+/" | sort -n
    pre-fix common typos alias ls-l="ls -l ";alias ll="ls -l"
    extract columns cut -c 8-15 file1 > file2
    text replace in file sed "s/word1/word2/g" file1 > file2
    del whitespace  lines sed '/^\s*$/d' tst.htm > tst2.htm
    multi file text replace
  • perl -i -pe 's/windows/linux/;' test*
  • find . -name '*.txt' -print | xargs perl -pi -e's/Windows/Linux/ig' *.txt
  • find -type f -name '*.txt' -print0 | xargs --null perl -pi -e 's/Windows/Linux/'
    		•
    Search all regular files for 'example' in this dir and below find -type f -print0 | xargs -r0 grep -F 'example'
    Find command that highlight the data you are looking for find server.log -type f -print0 | xargs -0 grep -i -n -I --max-count=50 --color=always DATA
    To find out the large files on a file system. find / -xdev -size +1024 -exec ls -al {} \; | sort -r -k 5
    To find and remove core files conditionally find ~ -name core -exec file {} \; -exec rm -i {} \; (the "-i" will ask you to say yes to remover the core file, safety first)
    List files by date. ls -ltr
    Find hidden files ls -a | grep "^\."
    Monitor messages in a log file tail -f /var/log/messages
    List paths that process id has open lsof -p $$
    List processes in a hierarchy ps -e -o pid,args --forest
    List processes by % cpu usage ps -e -o pcpu,cpu,nice,state,cputime,args --sort pcpu | sed '/^ 0.0 /d'
    Display selected user with top top -u geek
    List only specific process with top top -p 1390, 3656
    List all packages by installed size (Bytes) on rpm distros rpm -q -a --qf '%10{SIZE}\t%{NAME}\n' | sort -k1,1n
    Watch changeable data continuously watch -n 1 'cat /proc/interrupts'
    LOOK FOR A STRING grep "hello world" `find ./ -name "*" -print -exec file {} \; | grep text | cut -d ':' -f 1`
    Kill a User, the linux/unix way kill -9 `ps -aef|grep "USER" |awk '{ print $2 }'`
    RENICE CPU HOGS renice 20 `ps aux | sort -rn +3 -4 | head -1 | awk '{print $2}'`
    Replace string1 with string2 sed 's/string1/string2/g'
    To find pci devices use! With detailed information lspci -v
    Mount an ISO file linux mount -t iso9660 -o loop /home/user/file.iso /mnt/iso
    Security from users with big thumbs. touch -i ( in any directory that you would like to protect from"rm" If rm is run it would be with the -i option.
    Create an ISO disk image from a CD-ROM (sr0 being the cdrom) dd if=/dev/sr0 of=linux.iso bs=2048 conv=noerror,sync
    #Debian   Top
    apt-get update / apt-get upgrade First update the package lists / Then upgrade the packages
    apt-get install vim vim-runtime Install the full package vim and vim-runtime
    dpkg --remove vim Remove the package vim
    dpkg -l List installed packages, Debian/Ubuntu
    update-rc.d rc.local defaults Activate rc.local with the default runlevels
    update-rc.d -f rc.local remove Removes the rc.local from all runlevels
    #Suse   Top
    zypper refresh Refresh repositorie
    zypper install vim Install the package vim
    zypper remove vim Remove the package vim
    #Networking   Top
    Run command on $HOST as $USER (default command=shell) ssh $USER@$HOST command
    Run GUI command on $HOSTNAME as $USER ssh -f -Y $USER@$HOSTNAME xeyes
    Copy with permissions to $USER's home directory on $HOST scp -p -r $USER@$HOST: file dir/
    Forward connections to $HOSTNAME:8080 out to $HOST:80 ssh -g -L 8080:localhost:80 root@$HOST
    Forward connections from $HOST:1434 in to imap:143 ssh -R 1434:imap:143 root@$HOST
    Download a set of files to the current directory wget -r -nd -np -l1 -A '*.jpg' http://www.example.com/dir/
    Curl, use the -I flag to see the header and HTTP status code. curl -I google.ca
    Copy with permissions to $USER's home directory on $HOST scp -p -r $USER@$HOST: file dir/
    Copy with permissions to $USER's home directory on $HOST scp -p -r $USER@$HOST: file dir/
    Show status of ethernet interface eth0 ethtool eth?
    Manually set ethernet interface speed ethtool --change eth0 autoneg off speed 100 duplex full
    how to configure an IP address manually ifconfig eth0 192.168.1.10 netmask 255.255.255.0 broadcast 192.168.1.255
    Get your IP address ifconfig | grep "inet addr" | grep -v "127.0.0.1" | awk '{print $2;}' | awk -F':' '{print $2;}'
    Get your public IP address wget -qO- whatismyip.org
    Ping all hosts at once from your /etc/hosts file grep -v "#" /etc/hosts | awk '{print $1}' | while read host;do ping -c 1 $host;done;
    Adding and Removing a Network in Linux route add -net 10.125.0.0/18 gw 192.168.180.1
    route del -net 10.125.0.0/18 gw 192.168.180.1
    Use traceroute to track the route a packet takes on the internet traceroute FQDN or IPADDR
    List active connections to/from system netstat -tup
    Show network route netstat -nrv
    Show how many active connections there are to apache (httpd runs on port 80) netstat -an |grep :80 |wc -l
    Show if ssh is active netstat -ant |grep 22
    Lookup whois info for hostname or ip address whois FDQN/IPADDRESS
    Show network traffic except ssh tcpdump not port 22
    HTTP trafic only tcpdump -i eth0 -Xvvv port 80
    If you just want to capture FTP traffic with tcpdump tcpdump -i eth0 -vvv port ftp
    If you just want to capture FTP traffic to a file tcpdump -i eth0 -vvv port ftp -w ftp.pcap
    Scan computer with nmap nmap 192.168.0.1
    Scan entire Network for Netbios / SMB with nmap nmap -p 139 192.168.0.*
    nmap, Intense Scan nmap -T4 -A -v 192.168.0.1
    nmap, Quick Scan nmap -T4 -F 192.168.0.1
    Scan for valid TCP connections nmap -sT -T 5 -p 1-5000 192.168.0.1
    Output of nmap, greppable. nmap -p 23 192.168.0.* -oG telnet.txt
    Get the IP addresses dig FQDN A +noall +answer
    Get a list of all the mailservers dig FQDN MX +noall +answer
    Get a list of authoritative DNS servers dig FQDN NS +noall +answer
    Get a list of all the above dig FQDN ANY +noall +answer
    How to keep your computer from answering to ping! echo 1 > /proc/sys/net/ipv4/icmp_echo_ignore_all
    Route packets on Linux! echo 1 > /proc/sys/net/ipv4/ip_forward
    List interfaces ip link show
    List address of interfaces ip addr show
    Add (or del) ip and mask (255.255.255.0) ip addr add 192.168.0.1/24 brd + dev eth0
    ss - another utility to investigate sockets ss -s
    Using dstat for disk i/o, and network throughput dstat -dnyc -N eth0 -C total -f 5
    Using the time plugin together with cpu, net, disk, system, load, proc and topcpu dstat -tcndylp -M topcpu
    Very long output, on dstat behaviour dstat -taf --debug
    #OSX   Top
    Find cpu speed on the command line. sysctl machdep.cpu.brand_string
    As MacBook owner I have issues with heat, and one of the things I did was to disable "Spotlight" sudo mdutil -a -i off ; to re-enable: sudo mdutil -a -i on
    MacBook, heat issues! smcfancontrol ; Fan Control
    Applejack, troubleshooting assistant AppleJack
    A must for all Mac Users. QuickSilver ; Blacktree
    Clear you Mac's Cache! dscacheutil -flushcache
    Eject a Stubborn CD disktool -e disk
    Re-index Sportlight sudo mdutil -E / (then do this) sudo mdutil -i on /
    Add Spaces to Your Dock defaults write com.apple.dock persistent-apps -array-add '{"tile-type"="spacer-tile";}'
    Disable the Dashboard defaults write com.apple.dashboard mcx-disabled -boolean YES
    To lower the heat in a mac laptop, disable spotlight on the unit. sudo mdutil -i off /path-to-volume
    FrontRow is missing from Lion, I do not know why Apple have chosen to remove it! Here is how to get it back! FrontRow There is an issue with the new iTunes, but I mostly use it for movies!
    OS X MacPorts; Please use sudo for all commands
    port selfupdate Updates the tree
    port installed Shoes installed ported APPS
    port -f uninstall installed Un-installes Everything
    defaults write com.apple.finder AppleShowAllFiles YES Make all hidden files visible :-) Use at own discretion.
    Command-Shift-3: Take a screenshot of the screen, and save it as a file on the desktop
    Command-Shift-4 then select an area: Take a screenshot of an area and save it as a file on the desktop
    Command-Control-Shift-3 Take a screenshot of the screen, and save it to the clipboard
    Command-Control-Shift-4 then select an area: Take a screenshot of an area and save it to the clipboard, then past into doc
    #Windows   Top
    Management Console Shortcuts Control Panel Shortcuts
    • Computer Management -- compmgmt.msc
    • Disk Management -- diskmgmt.msc
    • Device Manager -- devmgmt.msc
    • Disk Defrag -- dfrg.msc
    • Event Viewer -- eventvwr.msc
    • Group Policies -- gpedit.msc
    • Shared Folders -- fsmgmt.msc
    • Local Users and Groups -- lusrmgr.msc
    • Performance Monitor -- perfmon.msc
    • Resultant Set of Policies -- rsop.msc
    • Local Security Settings -- secpol.msc
    • Services -- services.msc
    • Component Services -- comexp.msc
    • Security Center -- wscui.cpl
    • Display Properties -- desk.cpl
    • Firewall Settings -- firewall.cpl
    • Internet Options -- inetcpl.cpl
    • Network Connections -- ncpa.cpl
    • Sound and Audio -- mmsys.cpl
    • User Accounts -- nusrmgr.cpl
    • Power Options -- powercfg.cpl
    • System Properties -- sysdm.cpl
    • Add/Remove Programs -- appwiz.cpl
    • Automatic Updates Configuration -- wuaucpl.cpl
    When in a console window; Hit F7 for Command line history Use F1 to past previous command on character a time ; F2 followed by a number ; F3 for previous command
    #Links   Top
    Redhat Debian Backtrack Suse
    Tips 4 Linux Tips - Computer OSX Hints SUSE Tips & Tricks
    Microsoft sysinternals Windows Secrets Windows Computer Tricks
    #Virus-Security-Info   Top
    Top 10 Virus sophos Now Security, In the News Top 10 Virus Symantec Now
    Linux Security Issues Ubuntu Security Issues
    Microsoft Security Bullintin Microsoft Security Advisory Now

    Lennart Andersen