Welcome to the first in what I hope will be a series of quick tips and tricks collections. These collections will consist of one and two line commands that don’t warrant entire stand-alone tips to be written for them.
These tips are in no particular order….
Watch a log file as its appended to
tail -f logfile
Redirect a man page to a file
man whatever | col -b > whatever.out
Allow a command to continue execution after logout
nohup mycommand &
Extract tarball when tar has no z option
gzip -dc mytarball.tar.gz | tar xvf -
Display one particular line from a file
set linenumber = 8 # tcsh
linenumber=8 # ksh
sed -n "${linenumber}p" filename
Display current runlevel
who -r
Split lines of text into n-char lines
echo "some line of chars" | fold -w 3
Temporary directories
# /tmp gets cleared at boot, whereas /var/tmp does not
Insert spaces at beginning of each line in vi
:5,16s/^/ / # for lines 5 through 16, for example
Make init re-examine /etc/inittab
init q
Find out MAC address
arp `uname -n` # as regular user ifconfig -a # ethernet address only displayed when run as root
Display last 10 system reboots
last reboot | head
Set backspace to do the right thing
stty erase ^H # sometimes ^? - just do stty erase <hit backspace here!>
Linux – display /proc information
procinfo -a
Solaris – display processor information
/usr/sbin/psrinfo -v /usr/platform/`uname -i`/sbin/prtdiag | sed -n '/CPUs/,/Mem/p' | sed '/==/d'
Solaris – display memory information
/usr/sbin/prtconf | grep "Memory"
Solaris – display system information
/usr/platform/`uname -i`/sbin/prtdiag | more /usr/sbin/prtconf | more
Solaris – find out whether kernel modules are 32 or 64-bit
/usr/bin/isainfo -kv
Solaris – kill all matching processes – e.g. all “tip” processes
pgrep -l tip # check output.... pkill -x tip # -x to kill only full searchterm matched processes # for linux - man killall
Solaris – get syslogd to re-read config
pkill -HUP syslogd
Solaris – display numeric uid
/usr/xpg4/bin/id -u username
Solaris – crude halt….
sync;sync;sync;halt These tips are in no particular order.... CDE: Start a dtterm and log it dtterm -l -lf $HOME/logs/`date +%d%m%y`.log &
Truss a process from start of execution
truss -f -wall -rall -vall whatever
Truss an already running process and output to file
ps -ef | grep myprocess # find pid truss -f -wall -rall -vall -o outputfile -p pid
Execute command as different user
su - username -c "my;commands;here"
Stop users logging in
# kill user processes; then touch /etc/nologin
Set correct permissions on /tmp
chmod 1777 /tmp ls -lad /tmp # just checking!
View NIS hosts and passwd files
ypcat hosts ypcat passwd
Editing crontab
Only use crontab -e - signals change to cron daemon
Check which processes are listening on which ports
lsof -i | grep LISTEN
Print range of lines from a file
sed -n '100,200 p' filename
du without mountpoint traversal
du -kd /
tcsh: redirect stderr only – stupid c-based shells!
( command_here >/dev/tty ) >& /dev/null
tcsh: Stop any alias from being evaluated
\rm -rf / # i.e. preceed with backslash
Move last file modified
mv `ls -1 -t *.txt | head -1` whatever.txt
Get to telnet prompt from a telnet session
Ctrl-] # usually....
Disable ftp login for a user
echo "banned_username" >> /etc/ftpusers
ksh: Debug a script
ksh -x ./some_ksh_script.ksh
ksh: Set up r alias – see my article on customising your home environment for details (see /etc)
alias r='fc -e -'
ksh: Remove extensions from filenames
for file in *.ext; do
mv $file ${file%%.*}
done
Bourne-type shells: Find a file’s hard links
inode=`ls -li /path/and/filename | awk '{print $1}'`
find / -inum $inode -exec ls -li {} \;
ksh: Access positional parameters
$1 $2 # and so on, up to and including 9th param
${10} ${11} # params >= 10
ksh: Substitute old for new in current pwd then cd
cd old new e.g. $ pwd /path/to/foo/here $ cd foo bar /path/to/bar/here
Linux: Make image of floppy disk
dd if=/dev/fd0 of=/path/to/my/new.img Tail the newest file in a directory tail -f `ls -1rt | tail -1`
Find out which application caused a core dump
file /some/path/to/core
Sybase – Check status of databases
# su - sybase Password: > isql -Usa -Ppassword -w200 1> use master 2> go 1> select status, name from sysdatabases 2> go
Convert single column into two columns line by line
$ cat foofile a b c d e f $ paste -d: - - < foofile a:b c:d e:f
gunzip and untar with one pipe
gzip -dc SOMEFILE.tar.gz | tar xvf - # or with GNU tar tar xvzf SOMEFILE.tar.gz
Solaris: Standard UNIX ping
ping -s xxx.xxx.xxx.xxx
Simple command line arithmetic
echo " ( 10 + 20 ) / 15 " | bc
Solaris: Mount an ISO image located on NFS share
# mount -F nfs ip_address:/path/to/iso/store /mnt # lofiadm -a /mnt/my_iso.iso /dev/lofi/1 # mount -F hsfs /dev/lofi/1 /mnt2 # ls /mnt2 ...
Solaris: Set server to automatically boot
# Note - to reverse this either use eeprom or just bust # out with Stop-A # init 0 ok printenv # check auto-boot? ok setenv auto-boot? true ok boot
Quickly copy a directory tree with tar
cd /path/to/source tar cvf - ./* | ( cd /dest; tar xvf - )
Access the local shell from an ftp session
# note - this depends on your ftp client ftp> ! $ echo "Now in local shell"
Truncate a log file
# note - you might need to restart whichever process is # writing to the file... kill -HUP some_pid may be appropriate > /log/file # or cat /dev/null > /log/file
Solaris: Non-interactive pkgadd without admin files
pkgadd -d ${PKG_PATH} ${PKG} <<EOF
y
y
EOF
# obviously, your supplied input may need to be adjusted
Solaris: Check loaded kernel modules
modinfo | grep -i "whatever"
Add stuff to beginning or end of every line
sed 's/^/stuff/' file > newfile # at the beginning sed 's/$/stuff/' file > newfile # at the end
Solaris: Screwy vi behaviour when using console
# set TERM properly... TERM=sun-cmd export TERM
ksh: Using local environment file
# Ensure that you enter the following in your $HOME/.profile file
ENV=${HOME}/.kshrc
export ENV
Create tar archives where files have absolute paths
tar cvf foo.tar /path/to/files
Create tar archives where files have relative paths
cd /path/to tar cvf foo.tar ./files
Check if two files are hardlinked
ls -li file1 file2 # are inode numbers the same and the files
# residing on the same filesystem?
Recursive grep without GNU grep
find / -type f -name "*foo*" -exec grep "bar" {} /dev/null \; -print
Replace spaces in filenames with underscores
ls | while read file; do
mv "${file}" `echo "${file}" | tr ' ' '_'`
done
see differences between two files
diff file_1 file_2
# also see
man comm
count processes running on system (-1 to remove header)
echo $((`ps -ef | wc -l` - 1))
recursive wget
cd /where/to/put/files; wget -r http://somewhere.com/somedir
check number of fields on each line (delimited by |)
awk 'BEGIN {FS="|"} {print NF}' somefile
perform verbose nmap scan
nmap -v hostname
perform UDP scan
nmap -sU -v hostname
renice a process to increase priority
renice -10 -p 123
remove all .log files in /tmp that haven’t been modified in over two days
find /tmp -type f -name "*.log" -mtime +2 -exec rm -rf '{}' \;
indent output from a command
my_command | sed 's/^/ /'
Print last four characters in each line
awk '{printf("%s\n",substr($0,length($0)-3))}' foofile
output man page to file
man foo | col -b > outfile
view man page that’s not yet installed
nroff -man man_file | more
show unprintable characters with cat
cat -vET somefile
ls -l sorted by filesize
ls -l | sort -k5,5rn
extract a single file from a tar
tar cvf foo.tar single_file
ksh/bash change to previous directory
cd -
bash / ksh95 variable pattern substitution
$ FOO="bash"
$ echo "${FOO/ba/k}"
ksh
my standard useradd line
useradd -m -d /home/kwaldron -c "Kevin Waldron" -s "/bin/ksh" kwaldron && passwd kwaldron
perform snmpwalk of localhost
snmpwalk -v 1 localhost -c community_string | more
ksh – left pad numbers with zeros
$ typeset -Z8 foo $ foo=1234 $ echo $foo 00001234
find files larger than 300k
find / -size +300k -ls 2> /dev/null
find two different types of file extensions
find . \( -name "*.c" -o -name "*.c" \) -print
remove the first character from a variable
$ foo=12345
$ echo "${foo#?}"
2345
find what program has caused a core file
file /path/to/core
convert from ebcdic to ascii
dd if=/yourdir/your-ebcdicfile of=/yourdir/your-asciifile conv=ascii
replace current process with another (i.e. don’t fork, just exec)
exec newprocess
display unprintable filenames
ls -lb somedir
correct permissions on /tmp and /var/tmp
chmod 1777 /var/tmp # or chmod a=rwx,+t /var/tmp
recover corrupt terminal
stty sane echo "^O" # Ctrl-V Ctrl-O
ring the terminal bell
/usr/bin/echo "\a"
bash substitution in previous command
ls ^l^p ps
crontab location
/var/spool/cron/crontabs # solaris /var/spool/cron # linux
GNU grep
# show 2 lines either side of match grep -C 2 "somestring" filename # show 2 lines after match grep -A 2 "somestring" filename # show 2 lines before match grep -B 2 "somestring" filename
grep for a word
grep "\<something\>" somefile
GNU sed relative addressing
sed -n '/searchstring/,+2 p' filename # i.e. to print line containing searchstring plus the next two lines
convert dos file to unix (remove carriage returns)
dos2unix < infile.dos > outfile.unix # dos2ux on HP-UX tr -d '\r' < infile.dos > outfile.unix # the unix2dos command (ux2dos) exists for the opposite conversion # or just ftp the file in ascii mode in the first place, but beware that # all sftp transfers are binary only
searching for a literal $ in a file
grep '\$' filename # or fgrep / grep -F fgrep '$' filename
bash – funky curly brace substitution
ls file{1,3,4}
# to list file1 file3 and file4
ksh – alias r
alias r='fc -e -' # then r vi # will execute last vi command
copy directory tree
cd /src; tar cvf - ./* | ( cd /dest; tar xvpf - ) cd /src; find . -depth -print | cpio -pvdum /dest
show OS and kernel info
uname -a
wc -l without the filename
wc -l < filename
# or
wc -l filename | awk '{print $1}'
# as opposed to
wc -l filename
list mounts
mount # no arguments df -k
show my history
history
disregard alias
# rm -r dir rm: descend into directory `dir'? n # \rm -r dir
su and inherit user environment
su - [ user ] [ -c "commands ]
set terminal type
export TERM=vt100
ksh – concise tests
[[ -f foo ]] || {
echo "Foo doesn't exist" >&2
exit 2
}
traceroute using ICMP
traceroute -I destination
using last argument of previous command in bash
$ echo foohost foohost $ ping !$ ping foohost . . .
make an alias global for all users
- add entry to /etc/profile
check for listening ports
netstat -an | grep LISTEN
define sendmail smarthost for relaying in sendmail.cf
DSsomehost.foodomain.com
copy, preserving permissions, ownership and timestamps
cp -p source dest # recursively too cp -Rp source dest
create soft link
ln -s file_to_link link_name # hard link ln file_to_link link_name
create directories including non-existent parents
mkdir -p /some/lengthy/dir/tree
recursive chown
chown -R user:group /some/dir
recursive chmod
chmod -R 744 somedir
cut the last character from a string
a="somestring"
echo ${a} | cut -c${#a}
# other ways to do this
echo "${a#${a%?}}"
# or
echo "${a}" | sed 's/.*\(.\)/1/'
# or
echo "${a}" | nawk '{print substr($0, length($0))}'
# or
expr "${a}" : '.*\(.\)'
# or
echo "${a}" | tail -2c
truncate log file
cp /dev/null logfile > logfile cat /dev/null > logfile # may need to restart kill -HUP `cat /var/run/syslog.pid`
the true use of cat – to conCATenate files
cat file1 file2 file3 > finalfile
show subdirectories only in an ls listing
ls -l | grep "^d"
# recursively
find . -type d -exec ls -ld {} \;
show information about directory entry itself (not contents)
ls -ld dir # show size ls -ls # show inode numbers ls -lia
recursive grep
find . -type f -exec grep "somestring" {} /dev/null \;
sed to replace \ with \\
sed -e 's_\\_\\\\_g'
getent
getent hosts hostname
# using getent with ssh
ssh -l admin `get hosts hostname | awk '{print $1}'`
view available signals
kill -l
search for strings in a binary file
strings binary_name
show current runlevel
who -r (or on some Linuxen - runlevel)
show uptime and processor run queue averages
uptime # or with who output w
stop people logging in
touch /etc/nologin
temporarily change your prompt
PS1='$ ' export PS1
bourne based shells – show current environment variables
env # show all variables set # show shell options set -o # current shell options (set via set -x, etc) echo $- # bash shopt # show current shell echo $0
filename completion ksh (vi mode)
ESC-\
check for interactive shell
case $- in
*i*) echo "Interactive"
;;
*) echo "Not interactive"
;;
esac
find ip address for an interface
/sbin/ifconfig interface | grep inet # e.g. /sbin/ifconfig bge0 | grep inet
changing my primary group to one of my secondary groups
$ groups kwaldron wheel $ grep kwaldron /etc/group wheel:x:10:root,kwaldron kwaldron:x:502: $ newgrp wheel $ id uid=502(kwaldron) gid=10(wheel) groups=10(wheel),502(kwaldron) context=user_u:system_r:unconfined_t
gunzip and untar in one line
gzip -dc foo.tar.gz | tar xvf -
gzip and tar in one line
tar cvf - ./* | gzip -c > foo.tar.gz
with GNU tar this can happen in one command
tar xzvf foo.tar.gz tar cvzf foo.tar.gz files tar tvzf foo.tar.gz etc...
uncompress and untar
zcat foo.tar.Z | tar xvf -
find SUID files
/usr/bin/find / -perm -4000 -exec /usr/bin/ls -ld {} \;
find SGID files
/usr/bin/find / -perm -2000 -exec /usr/bin/ls -ld {} \;
find world writable files
/usr/bin/find / -perm -0777 -exec /usr/bin/ls -ld {} \;
# symbolic links will always be 77 so we can ignore them
/usr/bin/find -perm -0777 ! -type l -exec /usr/bin/ls -ld {} \;
remove files older than one week
/usr/bin/find /some/dir -name "*whatever*" -mtime +7 | xargs rm
find device files located where they shouldn’t be
/usr/bin/find / \( -type b -o -type c \) | egrep -v 'proc|/dev'
remove old core files (see Tip 0001 and Tip 0040)
/usr/bin/find / -name core -mtime +7 -exec rm {} \;
ksh/bash – damn emacs editing mode – turn it off!
set +o emacs set -o vi
remove duplicate occurrences of characters
# echo "ssoommeetthhiinngg" | tr -s [a-z] something ## remove all occurrences of characters # echo "ssoommeetthhiinngg" | tr -d [m-z] eehhiigg
check whois information for a domain
whois -h whois.opensrs.net foo.com
view dynamically linked library dependencies for a binary
ldd /path/to/some/binary
enable a service
vi /etc/inetd.conf # then kill -HUP `cat /var/run/syslog.pid` # or (Solaris) kill -HUP `pgrep syslogd`
remove a user, and their homedirectory
userdel -r someuser
check routing table
netstat -rn
check interfaces for collisions and errors, tx/rx packets, etc
netstat -ivn # check for just one interface netstat -ivn -I eth0
check NTP status
ntpq -p
perform a verbose trace of NTP
ntptrace -dv
ksh arithmetic – very flexible about variables
$ foo=1
$ bar=20
$ echo $(( foo + bar ))
21
$ echo $(( ${foo} + ${bar} ))
21
output to screen and file
my_command | tee -a /some/file
output to two files
my_command | tee -a /some/file > /some/other/file
append stderr and stdout to a file and then perform further actions
some_command 2>&1 | tee -a some_file | some_other_command > some_other_file
redirect stdout and stderr somewhere (in this case, /dev/null)
some_command >/dev/null 2>&1
place command in background
# either some_command & # or some_command ^Z bg # can then view jobs jobs # and kill by job number kill %1
line numbering
nl -ba infile > outfile
create 100kb file
dd if=/dev/zero of=/some/file bs=1 count=100
octal dump (show octal and ascii)
od -bc somefile # use this to check a directory entry od -bc somedirectory
show the arp cache
arp -a
view tracked alias cache (bash/ksh)
hash
clear tracked alias cache (bash/ksh)
hash -r
show all stty modes
stty -a
create a core dump
stty intr ^\ # then launch a process in the foreground and hit Ctrl-\
ksh read-only variables
# typeset -r somevar="something" # somevar="newval" ksh: somevar: is read only
using at
at now + 5 min at> ls at> ^D # then show list of jobs atq # linux atq output less verbose, but with simpler job identifiers atrm 1135911587.a # remove an at jon (Solaris) atrm 1 # ditto (Linux)
remove crontab
crontab -r
list crontab
crontab -l user # solaris crontab -u user -l # linux
exporting X
display_host# xhost + application_server# DISPLAY=mybox:0.0 application_server# export DISPLAY application_server# somexprog &
append a line to a file
echo "new line" >> some_file
apache control
apachectl restart # or /etc/init.d/httpd restart # or /etc/init.d/httpd stop && /etc/init.d/httpd start
take log of session
script /my/log/file
common vi(m) options
# ignore case :set ic # line numbers :set num :set nonum # turn off search highlighting (VIM) :nohl # syntax highlight on (VIM) :sy on # show unprintable characters :set list
view kernel message buffer
dmesg
check TCPD rules in /etc/hosts.{allow,deny}
grep -v "^#" /etc/hosts.allow /etc/hosts.deny | grep -v "^[ ]*$"
disable HTTP TRACE in apache
# vi /etc/httpd/conf/httpd.conf
# grep Rewrite /etc/httpd/conf/httpd.conf
RewriteEngine On
RewriteCond %{REQUEST_METHOD} ^TRACE
RewriteRule .* - [F]
# apachectl restart
get postfix to reload configuration
postfix reload
change user foo’s login name to bar
usermod -l bar foo view Group membership $ id -Gn -- anyuser anyuser wheel
tcpdump port 123 (ntp)
tcpdump port 123
disable SELinux protection for syslogd
# setsebool -P syslogd_disable_trans 1 ;; -P to make change permanent # getsebool -a | grep sys syslogd_disable_trans --> active # getsebool syslogd_disable_trans syslogd_disable_trans --> active
Display SELinux context in ls listings
ls -lZ /some/dir
Show all SELinux booleans
getsebool -a
is SELinux enabled?
selinuxenabled && echo Yes # or # getenforce Enforcing
view usb infomation
lsusb cat /proc/bus/usb/devices
submit a job for printing
lp -d destination filename
print cups status information
lpstat
xorg.conf
/etc/X11/xorg.conf xorgconfig
show partition table
/sbin/fdisk -l /dev/cciss/c0d0p1
check mouse is operational
cat /dev/mouse # then move the mouse
perform a reverse DNS lookup
host xxx.xxx.xxx.xxx dns_server_ip
Linux screenshots
# see http://www.troubleshooters.com/linux/index.htm import -window root -display servername:0 myfile01.pcx import -window root -geometry 640:480 -display servername:0 myfile01.pcx xwd -display servername:0 -root > myfile.dmp # can view with xwd | xwud
show inode information for all files in a directory
find . -type f -exec stat {} \;
root .profile under Linux
Most recent Linux distributions use a home directory for root of /root
You can check this with
# awk -vFS=':' '/^root/ {print $6}' /etc/passwd
/root
Again, most Linux distributions have root set up to use bash
# awk -vFS=':' '/^root/ {print $7}' /etc/passwd
/bin/bash
If you look in roots home directory, you'll see .bash_profile
# ls -la $HOME/.bash_profile
-rw-r--r-- 1 root root 234 Jul 6 2001 /root/.bash_profile
show multiple processor usage statistic
mpstat 1 10 # for ten iterations with 1 second interval
make a file immutable
chattr +i somefile
shutdown your system
init 0 shutdown -h now # reboot init 6 shutdown -r now
grub – boot in single user mode
# Hit the a key at the grub menu, then append 'single' to the list of # kernel arguments
add a log entry via syslog (will be directed as dictated by rules in /etc/syslog.conf)
# logger -p kern.error Test message # tail -1 /var/log/messages Dec 28 11:31:09 somehost root: Test message
get account password summary for a user
passwd -S username # e.g. # passwd -S kwaldron Password set, MD5 crypt # passwd -S ntop Password locked.
Vixie cron – increments
*/5 * * * * command (would mean every five minutes) # Vixie cron - ranges 10 0-5 * * * command (10 minutes past each hour from 00:10 'til 05:10)
set global library path
echo "/some/lib/path" >> /etc/ld.so.conf
# then run....
ldconfig
# can also do this on a session/user basis with
export LD_LIBRARY_PATH=${LD_LIBRARY_PATH}:/some/lib/path
chfn – change finger information
# e.g. /usr/sbin/useradd bob /usr/bin/chfn -f "Bob Smith" bob # could also use usermod -c "Bob Smith" # set the encrypted password... /usr/sbin/usermon -p 'abcd$01834HFB1a' bob
chsh can be used to change login shell
chsh -l # will list shells available in /etc/shells
curses based runlevel management
ntsysv
view CPU information
cat /proc/cpuinfo
view memory information
cat /proc/meminfo
check nic info
cat /proc/net/nicinfo/eth0.info
find out what type file is
file filename
module configuration file
# RHEL3 /etc/modules.conf # RHEL4 /etc/modprobe.conf
module commands
lsmod insmod rmmod depmod modprobe
remount a filesystem (e.g. mount read-only FS read-write)
mount -o rw,remount /some/mountpoint
mount an iso image
mount -t iso9660 -o ro,loop /some/foo.iso /mnt
grab last 10 lines of messages file
su - root -c "tail /var/log/messages"
use mii-tool on interface to gather link speed and duplex
mii-tool eth0
use ethtool for further information
ethtool eth0
set interface speed and duplex using ethtool
ethtool -s eth0 speed 100 duplex full autoneg off
display iptables policy
iptables -L
RHEL – display init.d scripts configured with chkconfig
chkconfig --list # set script to start in runlevels 2, 3, 4 and 5 chkconfig --level 2345 foosvc on # start the service service foosvc start
display filehandle usage
lsof
show current runlevel
runlevel
show /proc info for HBA
cat /proc/scsi/qla2300/0
show top processes ignoring inactive and zombie (i.e. running on CPU only)
top -i # run at highest priority with no delay top -q -i # using top in a script - batch mode top -b -n 1
pstree – kind-of equivalent to ptree
$ pstree -c -p -a -G PID # e.g. pstree of current shell process $ pstree -c -p -a -G $$ bash,24195 +-pstree,24858 -c -p -a -G 24195
show filesystem types in df output
df -kT
define kernel parameters
vi /etc/sysctl.conf man sysctl e.g. # /sbin/sysctl -a | grep shmmax kernel.shmmax = 33554432
set hardware clock to system clock date and time
hwclock --systohc
display memory usage (in megabytes)
free -m
ssh as different user than currently logged in user
ssh -l username hostname # or ssh username@hostname
basic scp syntax
scp /src/files user@host:/dest/path
List users accessing mounted filesystem
fuser -u /mnt
Kill all processes accessing this filesystem
fuser -km /mnt A big heap of (mostly) Solaris specific one-liners copy ACL from one file to another getfacl file_one | setfacl -f - file_two
Print all lp status information
lpstat -t
view the files that make up a Solaris package
/usr/sbin/pkgchk -l SUNWcsr | grep Pathname | sed 's/Pathname: \(.*\)/\1/'
check which package a file belongs to
/usr/sbin/pkgchk -lp somefile
snoop an interface for icmp
snoop -d eri0 | grep -i icmp
view a NIS+ map
niscat passwd.org_dir # for NIS ypcat passwd
backup to tape
tar cvf /dev/rmt/0n /some/crap mt rew tar tvf /dev/rmt/0n mt rew tar xvf /dev/rmt/0n single_file
Solaris 10 – list current zones
/usr/sbin/zoneadm list -cv
Solaris 10 – list current service state
svcs -a
Show extended information about a Solaris 10 service
svcs -xv svc:/network/nfs/client
Display all available information about a service
svcs -l svc:/network/nfs/status:default
List the services on which a Solaris 10 service depends
svcs -d svc:/network/nfs/client
List the services which depend on this Solaris 10 service
svcs -D svc:/network/nfs/client
View Solaris 10 inet services
inetadm
Convert new inetd.conf entries to new SMF format
inetconf
list users belonging to a group
listusers -g groupname
share a filesystem
share /some/fs # then on another system mount -F nfs some_ip:/some/fs /some/mnt # when we're done umount /some/mnt # then back on original system unshare /some/fs
find filesystem type
fstyp /dev/dsk/c0t0d0s0
set auto-boot to false
ok setenv auto-boot? false # or eeprom 'auto-boot?=false'
eject cdrom
umount /cdrom/cdrom0 eject cdrom # or if vold isn't running umount /mnt eject /dev/dsk/c0t6d0s0 (get this info from iostat -En)
Solaris DHCP configuration table management utility
dhtadm
DHCP Graphical interface
/usr/sadm/admin/bin/dhcpmgr
solaris print manager
/usr/sadm/admin/bin/printmgr
solaris graphical configuration
man fbconfig man m64config man kdmconfig # ia86
administer system controller
/usr/platform/`uname -i`/sbin/scadm
create windex with nohup -p
# catman & [1] 2345 # jobs [1] + Running catman & # nohup -p 2345 # exit
boot Solaris 10 in verbose mode
ok boot -m verbose
view disabled services on Solaris 10
svcs -a | grep disabled
disable / enable telnet
# disable telnet inetadm -d telnet # re-enable telnet inetadm -e telnet # or svcadm disable telnet svcadm -v enable -r telnet (-v verbose, -r recursively enable dependencies) # example # svcadm -v disable telnet svc:/network/telnet:default disabled. # svcadm -v enable -r svc:/network/ftp:default
shutdown your system
init 5 shutdown -y -g0 -i5 # reboot init 6 shutdown -y -g0 -i6
dynamically adding solaris interface
ifconfig hme0 plumb ifconfig hme0 192.168.0.2 netmask 255.255.255.0 broadcast + up route add default 192.168.0.1 # to make this permanent echo "hostname" > /etc/hostname.hme0 echo "192.168.0.2" >> /etc/inet/hosts # on Solaris 10 - ensure you modify /etc/inet/ipnodes too echo "192.168.0.0 255.255.255.0" >> /etc/inet/netmasks echo "192.168.0.1" > /etc/defaultrouter init 6
display tape drive status
mt -f /dev/rmt/0 status
find installed physical memory
/usr/sbin/prtconf | grep Mem
standard single user mode boot
ok boot -s # or init s # or reboot -- -s
power off
init 5 # or init 0 power-off # or shutdown -y -i5 -g0
single user mode cdrom boot
stop-A # or init 0 # then ok boot cdrom -s # on intel b -s (insert CD first, it will attempt to boot then give you a prompt)
show configuration information (controllers)
$ /usr/sbin/cfgadm Ap_Id Type Receptacle Occupant Condition c0 scsi-bus connected configured unknown c1 scsi-bus connected configured unknown c2 scsi-bus connected unconfigured unknown usb0/1 unknown empty unconfigured ok usb0/2 unknown empty unconfigured ok
burning cd’s under Solaris (see Solaris 10 Devices and Filesystems guide on docs.sun.com )
man cdrw man mkisofs
truss a process that’s already running (see strace on Linux)
truss -f -wall -rall -vall -o /some/outfile.out -p PID &
show kernel parameters for an interface ( <= Solaris 9 only )
netstat -k interface # e.g. netstat -k hme0
ping using alternative interface
ping -i bge1 somehost
ping 5 x 64 byte packets
ping -s somehost 64 5
Just added a new device to the system?
devfsadm # pre Solaris 8 this was tapes, disks, drvconfig # or touch /reconfigure init 6 # or reboot -- -rs # or init 0 ok boot -rs
mount an iso
# lofiadm -a /path/to/foo.iso /dev/lofi/1 # mount -F hsfs /dev/lofi/1 /mnt # umount /mnt # lofiadm -d /dev/lofi/1
show uname information in SCO format
uname -X
grab system diagnostics information and variables
/usr/platform/`uname -i`/sbin/prtdiag -v /usr/platform/`uname -i`/sbin/eeprom prtconf -D isainfo -kv # show kernel module version pagesize # show pagesize psrinfo -v # verbose processor information
Show loaded kernel modules
modinfo # other module commands modload modunload
Finding network parameters of bge interfaces
ndd -get /dev/bge0 link_status ndd -get /dev/bge0 link_speed ndd -get /dev/bge0 link_duplex
check metadbs
metadb
check metastat
metastat # view brief config snapshot metastat -p
view swap information
swap -l swap -s sar -r # view info n 5 samples at 5 second intervals sar -r 5 5
make 100M swap file to temporarily fix swap issues
mkfile 100m /export/swapfile swap -a /foo/swapfile swap -l swap -s # problem fixed - dodgy application patched or removed swap -d /foo/swapfile rm /foo/swapfile # if it needs to be made persistent, then add it to /etc/vfstab
wide ps listing
/usr/ucb/ps auwwwx
get CLOSE_WAIT interval
/usr/sbin/ndd -get /dev/tcp tcp_close_wait_interval
see if IP Forwarding is enabled
/usr/sbin/ndd -get /dev/tcp ip_forwarding
view information on signals
man -s3HEAD signal
fsck (on RAW device)
fsck /dev/rdsk/c1t1d0s0
view errors on devices (an easy way to find out device name of CD/DVD drives)
iostat -En
display inode to filename mapping
ff /dev/dsk/c1t1d0s0
display which processes have a file open (also works on some Linux distros)
fuser filename
display which files a process has open
pfiles PID pfiles `pgrep process_name`
Solaris 9 and above – reap zombie process
preap PID
show who is doing what
/usr/sbin/whodo
iostat
iostat interval iterations # e.g. iostat 1 10 # same can be done with prstat and vmstat
ptree – show parent/child process relationship
ptree PID # e.g. for current shell ptree `pgrep $( echo $0 | tr -d '-' )` # or ptree `pgrep $( echo $0 | sed 's/-//' )`
view current eeprom settings
/usr/platform/`uname -i`/sbin/eeprom
set MTU value for an interface
ifconfig interface mtu n # e.g. ifconfig hme0 mtu 1500 # place in hostname.interface file for persistence
show patch revisions
showrev -p patchadd -p
show brief listing of installed packages
pkginfo
show long listing of installed packages
pkginfo -l
see package info on a package that’s not yet installed
pkginfo -l -d /path/to/package.pkg
get package params (may aswell just browse /var/sadm/pkg/PKGname/pkginfo)
pkgparam SUNWcsr DESC
open Solaris product registry
prodreg
send a nohup to an already running command (Solaris 10)
nohup -p PID
define kernel parameters (requires a reboot after changes)
vi /etc/system
view current system parameters
sysdef | grep whatever # e.g. # sysdef | grep shar 1572864000 max shared memory segment size 100 shared memory identifiers (SHMMNI) 60 maximum time sharing user priority (TSMAXUPRI) # grep shmmax /etc/system *set shmsys:shminfo_shmmax=1258291200 set shmsys:shminfo_shmmax=1572864000
find pid if you know process name
pgrep some_process_name # or the obvious ps -ef | grep whatever # we can then ptree this ptree PID # or all in one ptree `pgrep process_name` Another bundle of miscellaneous one-liners (Misc OS's....) show process listing for single username ps -fu username
print all lines between two search terms (inclusive)
sed -n '/acd/,/anz/ p' file.dat
Solaris – show multiple processor statistics
mpstat 1 10
remove digits from a string
echo "abcd01234" | tr -d [0-9]
view MX record(s) for a domain
dig MX foo.com
GNU tar + bzip + exclude
tar cvpjf backup.tar.bz2 / --exclude /proc /dev /mnt /sys /media
create iso image
dd if=/dev/cdrom of=/some/iso.iso bs=512
# /etc/issue displayed before login
# /etc/motd display after login
ls by size in descending order
ls -la | sort -k5,5rn
show RPC info on a remote host (probe portmapper)
# rpcinfo -p remote.ip
output man page to file
man something | col -b > man.out
Add line numbers to a file
nl -ba < infile > outfile
Run syslog in Debug mode
/usr/sbin/syslogd -d
manual page detailing hosts.allow hosts.deny
man 5 hosts_access
display ps forest
ps -axf
recursively change permissions on directories only
find . -type d -exec chmod 755 {} \; -print 2>/dev/null
list specific users process info
lsof -u username
iconv convert between codesets
iconv -f UTF-8 -t iso85591 somefile
grab sar stats for specific time range
sar -A -s 19:40 -e 20:50 -f /var/adm/sa/sa21
Solaris 10 – checking online services
$ svcs -xv svc:/network/rpc-100235_1/rpc_ticotsord:default
svc:/network/rpc-100235_1/rpc_ticotsord:default (100235)
State: online since Mon Feb 20 12:59:06 2006
Impact: None.
$ inetadm | grep enabled
enabled online svc:/network/rpc/meta:default
enabled online svc:/network/rpc-100235_1/rpc_ticotsord:default
$ svcs -a | grep online | wc -l
46
Solaris: pgrep against full argument string
# sleep 200 & 5868 # pgrep sleep 5868 # pgrep 200 # pgrep -f 200 5868 #
recursive copy preserving permissions
cp -Rp /some/src /dest
using xargs to copy files
find /srcdir/ . -name '*.txt.gz' -mtime -2 | xargs -I {} cp {} /trgtdir/
ntp commands
# query $ /usr/sbin/ntpdate -q somehost # update # /usr/sbin/ntpdate -u somehost # show peers $ /usr/sbin/ntpq -p # show associations $ /usr/sbin/ntpq -c "assoc" # show rl vars for particular association $ /usr/sbin/ntpq -c "rl assID" # trace NTP back to primary source # /usr/sbin/ntptrace -dv someserver
Linux – view failure counts for all users
# faillog -a
Linux – show all pam_tally stats (failed login tally) – see Tip 0041
# pam_tally
Solaris – view PROM variables
eeprom | more
Solaris – echo ignoring backslash-escape sequences
-bash-3.00$ /usr/ucb/echo "c:\tuser\abc" c:\tuser\abc -bash-3.00$
Solaris 10: Is syslog enabled?
-bash-3.00$ svcs -a | grep system-log
Linux force NIC speed
mii-tool -F 100baseTx-FD eth0 # note - better to use ethtool as mii-tool only supports up to 100/FD ethtool -s eth0 speed 100 duplex full autoneg off # also, to use 1000/FD you must leave autoneg enabled
crypt
crypt < encrypted.file > unencrypted.file # crypt will prompt you for your key.
find the square root of a number
$ echo "sqrt(4)" | bc 2
Solaris 10: to enable tcp tracing on telnet
inetadm -m svc:/network/telnet:default tcp_trace=TRUE
Solaris 10: inetadm – list properties for selected instance
-bash-3.00$ /usr/sbin/inetadm -l svc:/network/login:rlogin
Solaris 10 – show faults
# fmadm faulty # fmdump -v
Linux – Change the label on an ext2 filesystem
e2label labelname
list available signals
kill -l
Linux – check Serial port config
# setserial -g -a /dev/ttyS0
set modification date on a file
touch -t DATE file # where DATE is in format [[CC]YY]MMDDhhmm[.SS]
octal dump of file
od -c file od -bc file
set system date on RHEL
date MMDDhhmm hwclock --systohc
send syslogd a HUP
killall -1 syslogd ;; linux pkill -HUP syslogd ;; solaris
fsck ext3 filesystem automatically answering Y to questions
fsck.ext3 -y /dev/hdb1
Linux – view PCI and USB bus attached devices
lsusb lspci
Solaris 10 – disable a service
# view dependencies svcs -a | grep gss svcs -d svc:/network/rpc/gss:default ;; gss depends on svcs -D svc:/network/rpc/gss:default ;; depend on gss svcadm -v disable svc:/network/rpc/gss:default svcs -xv svc:/network/rpc/gss:default svsa -a | grep gss
Linux – grep a gzipped file
zgrep "searchterm" foo.gz
show plain text strings within a binary file
strings /path/to/binary
stop and start named
rndc stop /etc/init.d/named start
strace
strace -f -o /var/tmp/trace.out -p 554 &
diff
diff file1 file2
using expr with multiplication
$ expr $a \* $b 20
Switch between postfix and sendmail on RHEL
/usr/sbin/system-switch-mail # rpm -qa | egrep -i 'sendmail|postfix|switch-mail' system-switch-mail-0.5.25-3 sendmail-8.13.1-2 postfix-2.1.5-4.2.RHEL4
Linux – view PCI devices
lspci
Linux – View USB devices
lsusb
Linux – Switch to another virtual console
Ctrl-Alt-F1
Solaris – display nickname to device translation table for eject
eject -n
Display all who information
who -a
join all lines in a file using paste
paste -d ' ' -s file1 > file2
Remove archived files that are over one day old
rm -f `find /archive/ -mmin +1440 -print`
awk substrings
echo "1234567890abcdefghij" | awk '{print substr($0,3,1) " " substr($0,11,8)}'
Some misc. Solaris one-liners
print PICL tree gathering temperature sensor info
/usr/sbin/prtpicl -c temperature-sensor -v
Clean up “dangling” /dev links
devfsadm -C
Installation log file
/var/sadm/system/log/install_log
detailed package info
pkginfo -l installed_package_name pkginfo -l -d some_unistalled_pkg.pkg
egrep for two things
egrep 'THIS|THAT' somefile
set erase char
stty erase ^H
run syslogd in debug mode to check configuration file
/etc/init.d/syslog stop /usr/sbin/syslogd -d ^C /etc/init.d/syslog start
pkgchk
-bash-3.00$ /usr/sbin/pkgchk -lp /usr/bin/man
NOTE: Couldn't lock the package database.
Pathname: /usr/bin/man
Type: linked file
Source of link: ../../usr/bin/apropos
Referenced by the following packages:
SUNWdoc
Current status: installed
svcs
# svcs -xv svc:/network/rpc/meta:default svc:/network/rpc/meta:default (SVM remote metaset services) State: disabled since Mon Jan 16 12:29:14 2006 Reason: Disabled by an administrator. See: http://sun.com/msg/SMF-8000-05 See: man -M /usr/share/man -s 1M rpc.metad Impact: This service is not running. svcs -Dv meta ;; that depend on this STATE NSTATE STIME CTID FMRI disabled - 12:29:09 - svc:/system/mdmonitor:default svcs -dv meta ;; this depends on STATE NSTATE STIME CTID FMRI online - 12:29:12 30 svc:/network/rpc/bind:default
Linux rules the heart of its users. This is enough a reason why one should embrace Linux 