•/etc/passwd Contains
the basics of a user
•/etc/security/.profile Providing the
user profile
•/etc/security/limits Contains all
the ulimits, or users' system resource limitations
•/etc/security/passwd Contains the AIX
user's password information
•/etc/security/user Contains
the most important settings
•/usr/lib/security/mkuser.default Contains
values used when creating user through mkuser
# getconf LOGIN_NAME_MAX To verify the setting in AIX
5.3 and later
# lsattr -El sys0 To
verify the setting in AIX 5.3 and later
# chdev -l sys0 -a max_logname=129 To change the
value of sys0
# mkuser xander To
create a user with default settings
# finger xander Gives
the short information of user
# chuser core=1048576 xander To change
the User attribute
# chsh xander To
change the user login shell
# chfn xander To
change GECOS information
# lsuser -f xander List
the user in stanza format
# passwd xander To
set or change password of user
# passwd -f xander To
change user GECOS using passwd command
# passwd -s xander To
change the user SHELL using passwd
# rmuser xander Remove
the user
# rmuser –p xander To
remove fully user information
•/etc/group Contains
the basics of a group
•/etc/security/group Contains
extended attributes to the specified group
# mkgroup atctest To
create a group
# mkgroup -a atcadmin To create an admin
group
# mkgroup adms=xander xangroup To create a
group and add Xander as the administrator of the group
# chgroup id=204 users=xander,atc,amdc xangroup Change the group's GID and add users
# chgrpmem Another
way to modify a group's members is with chgrpmem
# chgrpmem xangroup List the group
information
# chgrpmem -m - atc xangroup Remove a
user from a group
# lsgroup xangroup List
the info of group
# lsgroup -f xangroup List info of
group in stanza fromat
# rmgroup atctest Remove
the group
•/etc/security/environ Contains the
environment attributes for users
•/etc/security/lastlog Contains the
last login attributes for users
•/usr/lib/security/mkuser.sys Customizes
new user accounts
•/etc/security/login.cfg Contains system
default login parameters
•/etc/utmp Contains
a record of users logged into the system
•/var/adm/wtmp Contains
connect-time accounting records
•/etc/security/failedlogin Records all failed login
attempts
•/etc/motd Contains
the message to be displayed every time user login
•/etc/environment Specifies
the basic environment for all processes.
•/etc/profile Specifies
additional environment settings for all users.
•$HOME/.profile Specifies
environment settings for a specific user.
# ps -ef To
display all processes
# ps -f -l -ujim To
list processes owned by specific users
# ps -M To
list all the 64-bit processes
# kill 1095 To
stop a given process
# kill -kill 2098 1569 To stop
several processes that ignore the default signal
# kill -kill 0 To
stop all of your processes and log yourself off
# kill -9 -1 To
stop all processes that you own
# fuser -u /etc/filesystems List a process numbers
and user login names of processes
# fuser -k -x -u -c /dev/hd1 To
terminate all of the processes using a given file system
# fuser -kxuc /home To terminate
all of the processes using a given file system
# fuser -d /usr To
list all processes that are using a file that has been deleted from a given
file system
# fuser -xc /tmp List
open references within a specified file system
# find /home -type d -exec fuser -u {} \; Process is using a
directory within the file system as its current
working directory
# topas -i5 -n0 -p10 To view the
top 10 processes
The svmon command captures and analyzes a snapshot
of virtual memory
The svmon command creates nine types of reports
# svmon -G Global
Report
# svmon -U User
Report
# svmon -C Command
Report
# svmon -W Workload
Management Class Report
# svmon -T Workload
Management Tier Report
# svmon -P Process
Report
# svmon -S Segment
Report
# svmon -D Detailed
Report
# svmon -F Framed
Report
# aclget status To
display the access control information of status file
# aclput -i acldefs status To set the access control information
of status from acldefs
# aclget plans | aclput status To set
the access control information of status from plans
# acledit plans To
edit the access control information of the plans
#chown -R john:build /tmp/src To
change the owner & group of all files in the directory
# chmod 644 text To
use the absolute mode
#chgrp -R staff proposals Change the group
ownership of the directory named proposals
of dir stuff
# at -f filename -t CCYYMMDDhhmmSS Increment Submit a job to be run at a later
time
# at now -f appl/program > /dev/null
2>&1 To start at job
now
# atq List
the at jobs
# at -r root.1134169200.a Remove the at job
# ls /var/spool/cron/atjobs Location of at jobs
# ls -l /var/spool/cron/crontabs Location
of cron jobs
# crontab -l List
the all cron jobs
# crontab -e To
edit crontab file
# crontab -v username Lists the status
of the user's cron jobs
# crontab -r Remove
the crontab file
# crontab ~deploy/deploy.schedule Runs the
crontab file under user deploy
•/var/adm/cron/log The
cron daemon logs file
•/var/adm/cron/cron.deny Deny cron access to
user for cron schedular
•/var/adm/cron/cron.allow Allow cron access to
user for cron schedular
•/var/adm/cron/at.allow Allow cron access
to user for at schedular
•/var/adm/cron/at.deny Deny cron access
to user for at schedular
# telinit Directs
the actions of the init process
# telinit M Goes
into the maintainance mode
# telinit q Tell
the init command to reprocess the /etc/inittab
Normally, you do not need to restart srcmstr.
If the srcmstr daemon terminates abnormally, the respawn action specified in
the /etc/inittab restarts the srcmstr
daemon.
A command is a request to perform an operation or
run a program. A program or command that is actually running on the computer is
referred to as a process.
The common types of processes are:
Foreground and background processes
Processes that require a user to start them or to
interact with them are called foreground processes. Processes that are run
independently of a user are referred to as background processes. Programs and
commands run as foreground processes by default.
Daemon processes
Daemons are processes that run unattended. They
are constantly in the background and are available at all times. Daemons are
usually started when the system starts, and they run until the system stops. A
daemon process typically performs system services and is available at all times
to more than one task or user. Daemon processes are started by the root user or
root shell and can be stopped only by the root user. For example, the qdaemon
process provides access to system resources such as printers. Another common
daemon is the sendmail daemon.
Zombie processes
A zombie process is a dead process that is no
longer executing but is still recognized in the process table (in other words,
it has a PID number). It has no other system space allocated to it. Zombie
processes have been killed or have exited and continue to exist in the process
table until the parent process dies or the system is shut down and restarted.
Zombie processes display as <defunct> when listed by the ps command.
Ctrl-C To
intrrupt the process
Ctrl-Z To
stop process
# fg 589934 To
bring the process in to the foreground
# find / -type f > dir.paths & Run
the find command in the background
# nohup find / -type f & To run
the find command and leave it running after you log off in Bg
0 Represents standard input (stdin) <
1 Represents standard output (stdout) > or >> (append)
2 Represents standard error (stderr) 2> or 2>> (append)
2>&1 Redirects stderr to stdout.
1>&2 Redirects stdout to stderr
Performance Monitoring
# nice -10 foo Add
10 to current nice value (Lower Priority)
# nice -n 10 foo Add
10 to current nice value (Lower Priority)
# nice - -10 foo Subtract
10 from current value (Higher Priority)
# nice -n -10 foo Subtract
10 from current value (Higher Priority)
# renice -10 –p 563 Add 10 to default nice
value (Lower Priority)
# renice –n 10 –p 563 Add 10 to current nice value
(Lower Priority)
# renice - -10 –p 563 Subtract 10 from default
nice value (Higher Priority)
# renice –n -10 –p 563 Subtract 10 from current nice
value (Higher Priority)
# ps –ekl Long listing of kernel
processes with priority
# ps –L 483445 –l It
list the child the processes of parent process
# ps –kmo THREAD –p 16396 It list the threads of particular
processes
# schedo To
change the CPU usage priority decay rate
Context Switch : A
context switch is when one thread is taken off a CPU and another thread is
despatched onto the same CPU.
User
Mode : User mode is when
thread is executing its own application code or shared library code. Time spent
in user mode is reflected as %user time in output of commands such as vmstat,
topas, iostat, sar.
System Mode : System
Mode is when the CPU is executing code in the kernel. CPU time spent in kernel
mode is reflected as system time in output of vmstat, topas, iostat, sar
commands. Context switch time, system calls, device interrupts, NFS I/O, and
anything else in the kernel is considered as system time.
# time It
show the elapsed time in system and user mode
# vmstat 5 3
# vmstat -f To
display fork statistics
# vmstat -s To
display count of various events
# sar –P ALL 5 1 All
CPU related usage
# sar –q 5 3 Queue
details
# ps aux Locating
the dominant processes
# tprof –x sleep 60 Reports
processor usages
# lparstat 2 3 System
wide CPU report
# sar –P ALL 2 2 Viewing
CPU statistic with SMT
# sar -d 1 2 Disk
I/O statistic
# smtctl To
check SMT is enabled or not
# smtctl –m on –w now Tern on SMT
immediately
# smtctl –m on –w boot Tern on SMT at next
reboot
# bindprocessor –q To
check logical CPU
# iostat I/O
device statistics
# iostat -d hdisk2 2 Continuous
disk report
# netstat network
statistic
# netstat -rn Network
routing table
# netstat -rs Network
routing statistic
CPU bound A system is said to be CPU-bound if the total system (sy) and user
(us) CPU usage is approaching 100 percent. This would imply that idle time and
wait time for CPU are approaching zero.
Memory bound A system is memory-bound if some virtual memory is forced out to
disk, meaning the system is waiting on a relatively slow disk instead of
relatively fast RAM. This is indicated by a non-zero value in the page-in (pi)
and page-out (po) values.
Paging
rate is the
average number of page-ins and page-outs per CPU cycle.
Idle
time calculation:
Total CPU
Idle Time % = wait % + Idle Time %
Ex:
Average CPU
Idle Time percentage = ((99+1) + (97+2) + (95+4) + (99+1))/4 = 99.5%
