linux

puppet

2014-03-19T20:23:00.003-07:00

writing custom facts in puppet.

mcollective

Resource Abstraction Layer. (#puppet resource)

Puppet describe cron (describe everything about resource group)

noop

tools:

gepatto

start with small single purpose modules..

Configuration Management Maturity Model:

Artisian
Centralized
Normalized
Templated
Reusable --- hiera

Learn from Developers (Versioning) .. #subversion

Have a lab

##Investment ##

Oracle class

Perl Documents:

2014-02-18T03:58:00.002-08:00

http://docstore.mik.ua/orelly/perl3/prog/ch10_02.htm

http://www.tutorialspoint.com/perl/perl_modules.htm

Booting in Linux Rescue Mode

2013-07-09T06:22:00.000-07:00

1) Boot from DVD or other image file

2) Select rescue mode

linux rescue

linux rescue mpath

3) Once the rescue environment finishes booting, choose a language to use.

4) Select keyboard layout to use.

5) Wait for network interfaces to be located, and activate them, so that requested data can be transferred to another host.

6) The rescue environment will try to find the current Red Hat installation on the system. You will be prompted with the below options:

For this you will want to skip having Rescue Mode search for partitions. Make sure to boot into rescue mode to not automatically detect the partitions.

7) Use the fdisk -l command to find boot. This will be marked with an * <-- boot="" c0d0p1="" can="" cciss="" div="" either="" for="" is="" know="" mount.="" or="" sda1="" show="" something="" the="" then="" this="" what="" will="" you="">

8)If LVM is used:

Scan for metadata:

# lvm pvscan

# lvm vgscan

# lvm lvscan

# lvm lvdisplay to find out what lv is root

# lvm vgchange -ay /dev/volgroup to activate

May want to run fsck on these filsystems <---- div="" important="">

Then start creating the chroot environment:

1. #mkdir /mnt/sysimage

** # mount /dev/vg00/logvolroot /mnRescuet/sysimage **

2. #mount /dev/sd1 /mnt/sysimage/ <----root div="">

3. #mount /dev/dcciss/c0d0p1 /mnt/sysimage/boot <---- boot="" div="">

4. #mount /dev/cciss/c0d0p2 /mnt/sysimage/opt <---- div="" opt="">

Then you have to mount proc, sys, and dev regardless:

5. # mount -o bind /proc /mnt/sysimage/proc

6. # mount -o bind /sys /mnt/sysimage/sys

7. # mount -o bind /dev /mnt/sysimage/dev

8. # mount -o bind /usr /mnt/sysimage/usr

Then you should be able to chroot in.

9. # chroot /mnt/sysimage

Simple procedure to installing cups printer from Linux server:

2013-05-29T07:52:00.002-07:00

Searching for the required packages using yum

[root@pavan /]# yum search cups

Loaded plugins: product-id, rhnplugin, security, subscription-manager

Updating certificate-based repositories.

====================================================== N/S Matched: cups ======================================================

gutenprint-cups.x86_64 : CUPS drivers for Canon, Epson, HP and compatible printers

cups.x86_64 : Common Unix Printing System

cups-pk-helper.x86_64 : A helper that makes system-config-printer use PolicyKit

ptouch-driver.x86_64 : CUPS driver for Brother P-touch label printers

Name and summary matches only, use "search all" for everything.

[root@pavan /]#

Installing the packages..
[root@pavan /]# yum install cups.x86_64

Loaded plugins: product-id, rhnplugin, security, subscription-manager

Updating certificate-based repositories.

Setting up Install Process

Resolving Dependencies

Dependency Updated:

dbus-libs.x86_64 1:1.2.24-7.el6_3

Complete!

Install Hp Supported driver for cups printer.

[root@pavan /]# yum install gutenprint-cups.x86_64

Loaded plugins: product-id, rhnplugin, security, subscription-manager

Updating certificate-based repositories.

Setting up Install Process

Resolving Dependencies

--> Running transaction check

---> Package gutenprint-cups.x86_64 0:5.2.5-2.el6 will be installed

--> Processing Dependency: gutenprint = 5.2.5-2.el6 for package: gutenprint-cups-5.2.5-2.el6.x86_64

--> Processing Dependency: libgutenprint.so.2()(64bit) for package: gutenprint-cups-5.2.5-2.el6.x86_64

--> Running transaction check

---> Package gutenprint.x86_64 0:5.2.5-2.el6 will be installed

Complete!

[root@pavan /]#

Configuring cups

Just edit /etc/cups/cupsd.conf

Keep the following entries:

# Only listen for connections from the local machine.

Listen 172.50.0.95:631

Listen /var/run/cups/cups.sock

# Restrict access to the server...

Order allow,deny

Allow 192.168.0.0/16 10.0.0.0/8 62.243.72.0/24 127.0.0.1 (here add client vpn address)

# Restrict access to the admin pages...

Order allow,deny

Allow 192.168.0.0/16 10.0.0.0/8 62.243.72.0/24 127.0.0.1 (here add client vpn address)

open the port 631.

Service cups restart

Go to browser with ip address:

http://172.50.0.95:631/

Add the required printer & enjoy printing. ...

Linux Booting problems

2013-01-25T20:54:00.000-08:00

The Linux box not able to boot due to external file system errors

Loggin to single user mode # all file systems other than vg00

a.) interrupt the normal booting process & enter into grub menu
then choose the kernel version you want to boot select it press enter. choose the second line starting
with kernel and press e to edit. At the end of the line after one space put 1 (press enter key to save the changes) then b to boot in single user mode

b) After it prompts for logging password enter root password and mount root file system in read write mode

mount -o rw / or munt -o remount,rw /
cp -p /etc/fstab /etc/fstab_25jan
/usr/bin/vim /etc/fstab
(# all other file systems other than vg00)

reboot the server.

Linux kernel panic recovering through maintenance mode

Boot the Linux OS through installation media and select recovery .

Script For Searching alerts in Syslog and Dropping a mail

2013-01-25T20:41:00.000-08:00

#!/usr/bin/sh
#################################################################################
# Script Name : syslog_error_chk.sh #
# #
# Description : Searches for errors in syslog and mail . #
#################################################################################

LOG=/tmp/scsi_err.log
Se_file=/var/log/syslog/syslog.log
err1="error want to search"
err2="error want to search"

>$LOG

date +%Y"_"%b"_"%d"_"%H |awk -F '_' '{print $1,$2,$3,$4}'|while read cur_yr cur_mth cur_day cur_hr
do
srch_end_hr=0
srch_strt_hr=0
strt_day=0
srch_strt_mth=0
srch_strt_day=0
srch_string==0
if [ ${cur_hr} -lt 2 ]
then
#let srch_end_hr=${cur_hr}+1
#let srch_strt_hr=24+${cur_hr}-2
#let strt_day=${cur_day}-1
srch_end_hr=` echo "${cur_hr}+1"|bc `
srch_strt_hr=` echo "24+${cur_hr}-2"|bc `
strt_day=` echo "${cur_day}-1"|bc `
if [ ${strt_day} -eq 0 ]
then
case ${cur_mth} in
Jan) srch_strt_mth=Dec
srch_strt_day=31;;
Feb) srch_strt_mth=Jan
srch_strt_day=31;;
Mar) srch_strt_mth=Feb
leap_yr=` echo "${cur_yr}%4"|bc `
if [ "$leap_yr" -eq 0 ]
then
srch_strt_day=29
else
srch_strt_day=28
fi;;
Apr) srch_strt_mth=Mar
srch_strt_day=31;;
May) srch_strt_mth=Apr
srch_strt_day=30;;
Jun) srch_strt_mth=May
srch_strt_day=31;;
Jul) srch_strt_mth=Jun
srch_strt_day=30;;
Aug) srch_strt_mth=Jul
srch_strt_day=31;;
Sep) srch_strt_mth=Aug
srch_strt_day=31;;
Oct) srch_strt_mth=Sep
srch_strt_day=30;;
Nov) srch_strt_mth=Oct
srch_strt_day=31;;
Dec) srch_strt_mth=Nov
srch_strt_day=30;;
*) echo "Invaild Current Month" ;;
esac
else
#let srch_strt_day=${strt_day}
srch_strt_day=` echo ${strt_day} `
srch_strt_mth=` echo ${cur_mth} `
fi
if [ ${cur_hr} -eq 1 ]
then
egrep "${err1}|${err2}"" $Se_file|grep "${srch_strt_mth} ${srch_strt_day} 23" >>$LOG
egrep "${err1}|${err2}"" $Se_file|grep "${cur_mth} ${cur_day} 00" >>$LOG
egrep "${err1}|${err2}"" $Se_file|grep "${cur_mth} ${cur_day} 01" >>$LOG
else
egrep "${err1}|${err2}"" $Se_file|grep "${srch_strt_mth} ${srch_strt_day} 22" >>$LOG
egrep "${err1}|${err2}"" $Se_file|grep "${srch_strt_mth} ${srch_strt_day} 23">>$LOG
egrep "${err1}|${err2}"" $Se_file|grep "${cur_mth} ${cur_day} 00" >>$LOG
fi
else
#let srch_end_hr=${cur_hr}+1
srch_end_hr=` echo "${cur_hr}+1"|bc `
#let srch_strt_hr=${cur_hr}-7
srch_strt_hr=` echo "${cur_hr}-2"|bc `
#let srch_strt_day=${cur_day}
srch_strt_day=` echo "${cur_day}" `
srch_strt_mth=${cur_mth}
if [ ${srch_strt_hr} -lt 10 ]
then
srch_strt_hr=` echo "0${srch_strt_hr}" `
fi
if [ ${srch_end_hr} -lt 10 ]
then
srch_end_hr=` echo "0${srch_end_hr}" `
fi
while [ $srch_strt_hr -lt srch_end_hr ]
do
egrep "${err1}|${err2}" $Se_file|grep "${srch_strt_mth} ${srch_strt_day} ${srch_strt_hr}" >>$LOG
srch_strt_hr=`echo "${srch_strt_hr}+1"|bc`;
if [ ${srch_strt_hr} -lt 10 ]
then
srch_strt_hr=` echo "0${srch_strt_hr}" `
fi
done
fi
count=` cat $LOG|wc -l `
if [ ${count} -gt 0 ]
then
mailx -s "SCSI read and write errors from '$(hostname)'" xyz@gmail.com < $LOG
fi
done

Unix Interview Questions

2013-01-24T04:09:00.001-08:00

How to convert a ext2 file system to ext3 ?

What modprobe will do in Linux ?

what is the use of kudzu ?

@@@@@@@@@@@@@@@@@@@@@@@@@@@
@@@@@@@@@@@@@@@@@@@@@@@@@

How to print two files columwise in third file ?

paste -d' ' file1 file2

How to check different error count in a log file ?

Maintain error count record and if the error count is more than previous ignore. if the error count is less than previous reset the counters.

How to reverse a string or check weather its a palindrome or not ?

string_new = rev string1 #### it gives the reverse of the string.
test string_new = string1; if [$? -eq 0] ;then do echo "its a palindrome";fi

########################################################3

1) Tell me about yourself ?

2) tell me your day to day activities ?

3.) replacing a boot disk ?

4) patching HP-Ux ?

5) Hardware models you worked on ?

6) processor of Hp9000 series ?

7) How do you trouble shoot ?

8) script to cut a particular field ?

9) script to print a file reversely ?

tail -r myfile.txt

or
tac reverse of cat

tac myfile.txt

10) perl scripting exp >. ?

11) Disk addition ?

12) Disk addition in cluster ?

13) creating a software depot ?

14) checking model /

15) do you have any specific questions ?

***************************************

Tell me about your work .. ?

Rate yourself in Perl Scripting and Shell scripting ?

How you write modules in puppet ?

About exadata & Data Ontap ?

Perl Scripting:

-- > Autoloader ?

---> Difference between a module and package ?

Tell me about your environment in puppet ?

How to configure password less ssh ?

Any Other Questions to Ask ?

*************************************
***********************************
Tell me about yourself?

How do you rate on scale of 1-10?

Hp Service Guard?
How to configure a package?

How do you mirror lv?

How do you restore a failed disk?

what is major number ? minor number ?

What are the contents of /etc/resolv.conf ?

Significance of /etc/nsswitch.conf ?

How do you check Newtwork interface speed ?

How do you evoluate system performace ?

Programming .. ?

what is the o/p of "echo $$"?

write a simple for loop ?

Any idea on ldap ? How to configure ldap ?

What are the backup tools present in your environment ?

                                                                     
                                                                     
                                                                     
                                             
� Is your current system more BSD or System IV based
and why?

� How do you boot into single user mode?

� What are the options for the shutdown command?

� What is the su du command used for?

� What is a super block?

� What command do you use to access the Super Block?

� What is the difference between a symbolic and hard
link? When would you use each?

� What directory holds file with the sticky bit and
when is it used?

� What command do you use to change file ownership and
privileges?

� What is another name for the kill command?

� What is the default value if you put no options on
the kill command?

� What is the letter equivalent of the -9 and -15
options?

� What are the nice and renice commands used for?

� What are the 7 fields in the /etc/passwd file? (on 1
line)

� What command do you use to create a device? What are
the 2 numbers associated with it?

� What are the termcap and terminfo commands used for?

� What is /etc/remote file used for?

� What command or tool do you use to format a disk?

� How do you create a mount point for a disk
partition?

� How do you create a file system on a new disk?

� Why wouldn't you use default options on mkfs?

� What it the lost+found directory and where does it
live?

� Name 3 tape mediums for backup

� What is a level 0 backup?  Level 1?  Level 2?

� Where is the backup info kept?

� Other than dump, name 2 other backup commands.

� What is SYSLOG? How does it work?

� What is a loadable kernel module?

� What is the difference between a classful and
classless IP address?

� What is the difference between the ARP and Reverse
ARP commands?

� What is a subnet mask?

� What is a default router? Where is used?

� What protocol does ping use?

� What is the difference between a hub, a switch, and
a router?

� What is the difference between DNS lookup and
reverse DNS lookup?

� What is PPP?

� Do you use USENET?  What version of Sendmail?

� Name 3 deamons on a UNIX system.

� What deamon is the system master deamon?

� What is the portmap deamon?

� What is the difference between x-server and
x-client?

1. What is the difference between .xinitrc and .xsession?




2. What is the difference between a gateway and a router?



3. Describe your experience with Microsoft Windows registry?



4. How many SCSI devices can be connected to a workstation with one single
   channel SCSI-2 controller?


5. Name the basic data types in PERL.


6. What must a text file begin with to be recognized as postscript code?


7. What does the UNIX gutinteg command do?



8.  What files, ownerships and permissions must be set for rsh to work without
    a password?



9.  How do you calculate the total number of blocks or sectors available on
    a disk?


10. If a SCSI hard drive was formatted on a SUN workstation and no data has
    yet been written to it, what needs to be do to use it on a non -SUN Linux 
    system?


11. Describe an SNMP application you have developed.




12. Describe the procedure for permanently modifying the initialization string
    on a modem connected to a Cisco termianl server.


13. In what subdirectory is the X windows hardware configuration file 
    XF86Config found on a system configured with Linux?


14. Describe some of the software project management tools you have used.



15. What is the path to the shutdown command on a DEC Alpha running OS/F?


16. Name the seven most important tools a System Administrator uses?





17. Describe methods you have used to assure completion of projects on 
    schedule. 



18. How would you set up cron entries for a non-priviledged account?


19. What is the path to the sendmail configuration file?


20. How would you remove all the core files on a filesystem.


21. What is the difference between Cnews and INN?


22. Briefly describe the sequence of events when printing a file under BSD..



23. What do the options 2755 mean to chmod?


24. What is RAID level 5? Level 0?


25. Describe the steps, tools and procedures you have used in project 
    management.




26. Describe the most complex client/server anomaly you have encountered and 
    how you solved it.




27. Describe your experience in forecasting server load and equipment 
    replacement.




28. What were your considerations in specifying a PC hardware standard?





Applicant Name:

Date:

how familiar are you with win32 programming/administration




how familiar are you with UNIX programming/administration




What do you consider good debugging techniques




What do you consider good system administration techniques




would you work better with set schedule or work on your own time




What classes/projects/experiences have you done that you think may help you




How comfortable are you ripping apart machines




Are you familiar with RAID/SCSI systems


1) What is the first line of defense in system security?




2) What should be used to maintain the /etc/shadow file?





3) What is the default shell for the "root" logonid?  What other shells
are acceptable for this logonid?





4) What is the function of the kernel?





5) Using the Bourne shell syntax, show the command that sets the PATH 
environment variable to look in /usr/bin first, /usr/local/bin second,
and the current directory last.





6) Show the command to search for any files or directories with question 
marks in their names.





7) Which of the following commands redirects output to a file?

 rd somefile > test
 cat somefile > test
 cat somefile >> test
 cat somefile | test


8) You are using "vi" to edit a file with multiple pages.  Which command
will take you down one page the fastest?





9) What command do you use to quit "vi" without saving changes?





10) Which command do you use to display a directory listing of files, 
including the file type?





11) What is the command to display on-line help for a unix command?





12) To display a list of all manual pages containing the keyword "date", what
command would you type?





13) What command will display the first 10 lines of a file called "junk"?





14) What file will tell you where system log files are being written (if any)?




15) What command diplays a full listing of processes, including headers?





16) How do you terminate a process?





17) Using symbolic mode, add group write permissions to the file "junk".
 Do the same using octal mode.





18) In the following, where does the output for standard error go?

 /usr/lib/sendmail -OQueueSortOrder=host -oQ/var/spool/mqueue-8h \
    -q >> /var/adm/log/mqueue-8h 2>&1





19) What is the command to check the available free disk space on all local
filesystems?  Which operating environment does the syntax used apply to?





20) You have need to configure a new network client and have been given the IP
128.194.49.48128.194.49.48 in the 128.194.48.0/23 subnet.  You configure the machine
with that IP and set the default router as you were told but are not
getting packets or response to pings.  What is probably wrong?






21) Describe the X Window system client/server model.









22) Please list and describe 2 or more authentication mechanisms when displaying
X applications on remote displays.  Which one is "better" in terms of
security?





23) You added a line to /etc/aliases, but it doesn't seem to be working.  Why?




24) You commented out a server in inetd.conf, but it's still active. Why?





25) What's a process? What's an inode? Describe the difference between a
symlink and a hard link.





26) Name as many shells as you can.





27) How do you plan to document changes to this environment?





28) You have a problem and you don't know how to solve it.  Name all the
resources you can think of that you might consult.





29) What have you done recently that you particularly liked, or are proud of?





30) I have a file named 'dash fr' (-fr); how do I get rid of it?





31) Why did I just ask that question?





32) What's the difference between a library function and system call?





33) The command to see who is on the system is:

  who
  what
  why
  where


34) Which commercial UNIX platform dominated the computer industry?

  FreeBSD
  Microsoft McUnix
  Solaris
  HP-UX
  Linux


35) In which file is the default router address kept?

  /etc/resolv.conf
  /etc/nsswitch.conf
  /etc/hosts
  /etc/defaultrouter


36) The first field field in an /etc/passwd entry is:

  The uid
  The name
  The gid
  The home directory.


37) According to POSIX.2, which of the following tests to see if file foo 
exists and is readable?

  test -f foo
  test -r foo
  test -w foo
  test -x foo


38) According to POSIX.2, which option tells sort to compare the keys in a
case-insensitive manner?
  
  -c
  -f
  -i
  -v


39) The renice command may alter the priority of:

  A single process
  All process in a process group
  All processes owned by a user
  All of the above


40) To setup a master/slave NIS system such that the slave takes over lookup
requests when the master crashes:

  run ypserv on the master; ypbind on the slave
  run ypserv,ypbind on the master; ypset on the slave
  run ypserv,ypbind on the master; ypserv,ypbind on the slave
  run ypserv on the master; ypserv -s on the slave


41) You boot a client machine and attempt to mount an NFS drive from the
server.  The NFS mount worked yesterday, and neither the server nor its NFS
export list has been modified since then.  The mount command just hangs.
Where do you look for the problem?





42) Acceptable levels of bad nfs calls fall under what percentages?

  10-15%
  1-2%
  45-55%
  anything under 90%


43) When debugging a core in gdb, what does the command "bt" give?

  the core memory
  heap usage
  the calling stack


44) Please describe the complete boot process for a Unix system (your choice,
but preferably Sun if known).  Start at the moment the power switch is
turned on.












 
45) What is the main negative aspect of telnet/rshell/rlogin with respect to
security?  Please list 2 or more mechanisms of overcoming that aspect.








46) How many devices can be attached to a SCSI/SCSI-2 bus?  A "wide" SCSI bus?





47) A user performed a "cd;chmod 644 ." before logging out.  What problem
occurs when they log in the next time, and what level of priviledge is
required to correct the problem?





48) Please describe the path and types of programs that handle an e-mail message
starting from when a system receives the first packet of information until
the recipient reads it.










49) A customer has created a web page and complains that attempts to view
it result in "forbidden" messages.  What is the main problem?  Directory
listing is as follows:

# ls -al
total 240
drwxr-xr-x   2 joeuser   other        8192 Apr 19 17:54 .
drwx------  57 joeuser   other        8192 Apr 16 14:13 ..
-rw-------   1 joeuser   other        6311 Apr 19 17:50 back.xbm
-rw-------   1 joeuser   other        9650 Apr 19 17:50 daemon.gif
-rw-------   1 joeuser   other       11230 Apr 19 17:50 ferret.jpg
-rw-------   1 joeuser   other       11925 Apr 19 17:50 giraffe.gif
-rw-------   1 joeuser   other       32760 Apr 19 17:50 help.gif
-rw-r--r--   1 joeuser   other         967 Apr 19 17:46 index.html
-rw-------   1 joeuser   other        3871 Apr 19 17:50 kewl.jpg
-rw-------   1 joeuser   other        9018 Apr 19 17:50 luser.jpg
-rw-------   1 joeuser   other        2143 Apr 19 17:50 news.gif
-rw-------   1 joeuser   other        9055 Apr 19 17:50 noms.gif
-rw-------   1 joeuser   other        3071 Apr 19 17:50 race.gif
-rw-------   1 joeuser   other        3301 Apr 19 17:50 sailbot.jpg
-rw-------   1 joeuser   other       10511 Apr 19 17:50 tamu.gif
-rw-------   1 joeuser   other       19696 Apr 19 17:50 tsip.jpg
-rw-------   1 joeuser   other        6376 Apr 19 17:50 unix.gif
-rw-------   1 joeuser   other        2267 Apr 19 17:50 xray.gif
-rw-------   1 joeuser   other        3858 Apr 19 17:50 zoom.jpg






50) What happens when you issue the following commands (as root):

 # kill -1 1


 # kill -1 -1


 # init 0


 # sync


 # rm /dev/console

Useful links

2013-01-12T01:53:00.000-08:00

Redhat LVM

https://access.redhat.com/knowledge/docs/en-US/Red_Hat_Enterprise_Linux/5/html-single/Logical_Volume_Manager_Administration/index.html

https://access.redhat.com/knowledge/docs/en-US/Red_Hat_Enterprise_Linux/4/html/System_Administration_Guide/s1-rescuemode-booting-single.html

Linux SAN and devices:

http://www.swissunixsupport.com/tips/linuxsan

Solaris file system:

http://www.hyborian.demon.co.uk/notes/vx_cli.html

http://www.tek-tips.com/viewthread.cfm?qid=323113

Hpux Bad disk:

http://bizsupport2.austin.hp.com/bc/docs/support/SupportManual/c01911837/c01911837.pdf

http://kmit4u.blogspot.dk/2010/06/unix-hp-ux-how-to-check-bad-disk.html

Hpux upgrade:

http://h71028.www7.hp.com/enterprise/downloads/5667-Henderson_transcript.pdf

Hp Service Guard Cluster:

http://www.pearsonhighered.com/samplechapter/0131463969.pdf

http://mailsinto.blogspot.dk/p/cluster-commands.html

http://ktkb.wordpress.com/category/hp-ux/

http://docstore.mik.ua/manuals/hp-ux/en/B3936-90122/ch07s01.html

Hp Ux Troubleshooting:

http://bizsupport1.austin.hp.com/bc/docs/support/SupportManual/c01942679/c01942679.pdf

http://h20000.www2.hp.com/bizsupport/TechSupport/SupportTaskIndex.jsp?lang=en&cc=us&taskId=110&prodTypeId=18964&prodSeriesId=5103987

Hp Ux Network Speed:

http://www.symantec.com/business/support/index?page=content&id=TECH15108

http://h30499.www3.hp.com/t5/System-Administration/How-to-check-the-speed-of-network-interface-in-HP-Unix-server/td-p/3900628

Capacity Request for LVM (Hp ux and Redhat)

2012-09-09T09:09:00.000-07:00

Types:

Linux Normal::

1. discover new disk by scanning hbas (vendor specific scripts ) or echo "- - -"
2. then use fdisk
3.pvcreate /dev/rdsk/C0t1d23
4.mknod
5.vgcreate
6.lvcreate
b.) makefs
7.mount

##################for existing lv ##########
vgextend
lvextend
extend2fs or resize2fs depending on the version which supports

Linux Cluster::

For Cluster follow the same procedure ..

we have to restart cluster service in other node
service cmcld stop/start

Hp-Ux Normal:

1.) take ioscan out put to one file & then do insf -c disk to discover the disk
2.) take ioscan out put and compare to find new disks
3.) pvcreate /dev/rdsk/cxtydz
4.)vgcreate
5.)lvcreate
6.)makefs
7.)mount

##################for existing lv ##########
vgextend
lvextend
fsadm or extendfs depending on the version which supports

Hp-Ux Cluster:

Follow the above steps . . if extended vg then we have to do vgexport in preview mode and in other node we to export the vg and we have to import again with new map file.

Node 1: (active)
vgexport -p -v -s -m old.dsk old.map /dev/testvg
scp old.map node2:/

Node 2:
vgexport /dev/testvg
vgimport -m old.map -s /dev/testvg

Hp-Ux BCV / GBCV :

We have to mask the corresponding BCV / GBCV luns

Common Problems::

1.) File system is 100% utilized..
a) then we have to extend small amount
b) Free up some space to write
2.) Number of free PE s completed
3.) Need to defragment the file system

grep -r in Hp-Ux // Recursive grep in Hp-Ux

2012-04-04T22:36:00.001-07:00

We can use the below script to search recursively in hp-ux. We can added this to path. so that we can run it directly any time.

#!/usr/bin/sh
typeset DIR=$1
typeset PAT=$2
find ${DIR} -xdev -type f | while read FILE
do
[ `file ${FILE} | grep -c ascii` -eq 0 ] && continue
grep "$PAT" ${FILE} /dev/null
done
exit 0

...run as:

# ./temp /path pattern

Send large files to email from linux box

2011-12-20T22:44:00.000-08:00

uuencode:

we can send large files to email from linux box using this command.

Syntax:

uuencode file-name file-name|sendmail -v mailid@mail.com

uuencode file-name file-name|mailx -s "some-file" mailid@mail.com

UNIX95

2011-06-13T06:11:00.000-07:00

################################################################################

UNIX95

UNIX95= ps -eo pid,user,sz,vsz,args|sort -nbk3|tail -20 (it will sort according to third field i.e sz)

UNIX95= ps -ef -o pid,ruser,vsz,args|sort -nrk3

UNIX95= ps -eo pid,user,sz,vsz,pcpu,args|sort -nbk5 | tail -10 (for cpu)

UNIX95= ps -eo pid,user,sz,vsz,args|sort -nbk3|tail -20

UNIX95= ps -eo pid,user,sz,vsz,args|sort -nbk3|grep -i 'LOCAL=NO'|wc -l

#################################################################

GBL_MI_LOST_PROC is greater than zero.

2011-06-13T06:09:00.000-07:00

#view /var/opt/perf/status.scope
GBL_MI_LOST_PROC is greater than zero:
**** 06/11/11 00:35:00 ****
Server collector startup completed, beginning data collection.
Collection intervals: Process = 60 Global = 300
Warning: GBL_MI_LOST_PROC is greater than zero.
**** /opt/perf/bin/scopeux : 06/11/11 23:30:00 ****
Start of /var/opt/perf/datafiles/logproc file roll
**** /opt/perf/bin/scopeux : 06/11/11 23:30:24 ****
Successfully rolled /var/opt/perf/datafiles/logproc.
@@@@@@@@@@@
ref:
GBL_MI_LOST_PROC:-
The number of processes the measurement layer has lost the ability to update during the interval. This is an indication the
system activity might require the midaemon be restarted with a larger process count. See the midaemon man page for additional
information on the -pids parameter.
man midaemon
18:root [/var/opt/perf] file status.mi
status.mi: ascii text
18:root [/var/opt/perf] cat status.mi|tail -30

http://forums11.itrc.hp.com/service/forums/questionanswer.do?admit=109447626+1307944817619+28353475&threadId=1174457
##################################################################################

BCV(Business Continuity Volume)

2011-06-10T19:57:00.001-07:00

EMC for DBA's

Symmetrix refers to the EMC disk devices, disks within thid symmetix can be divided into various sized logical volumes, these logical volumes can be logicaly joined together and presented to a server.

There are 2 types of logical volume:

Hypervolumes - range of continuos space on a single disk. A single disk can be divided into 128 parts or hypervolumes this is refered to as slicing or splitting. These now form the basis to create metavolumes.

Metavolumes - A group of hypervolumes of the same size grouped together, this is then presented to a server. Once part of a metavolume, only the whole meta can be presented to the server not single disks.

Meta Head and Tail

When hypervolumes are added to a metavolume they are given a sequence, the first hyper being the head and last being the tail. Data is written to Meta from head to tail.

Concatenated Metavolume

Writes data to one hypervolume at time until it becomes full, then moves onto the next

Striped Metavolume

Data is written to metavolume in multiples of cylinder size. The first write will go to first meta (head), then the next write to the next meta and so on. Amount of data written to the hypervolume depends on the stripe size. The stripe size is based on being a minimum of 2 cylinders. A cylinder is 480K so minimium stripe size is 960K.

Server disks in EMC are usually refered to as R1 disks, copies of these disks will be known as R1 BCV disks. Remote disks kept in sync with SRDF would be called R2 disks.

BCV

A BCV (Business Continuity Volume) is a mirrored on demand set of disks. This is usually used for backup purposes to capture a copy of a database. With a cold BCV backup the Oracle database would be shutdown first. With a hot backup 2 disk volumes assocated with the BCV would be defined. The database would be put in backup mode the a snapshot of disk volume 1 would be taken that contained all the datafiles. After this a log switch would occur then a snap shot of the second disk volume that contained all the archive logs would be taken.

SRDF

This is a remote in sync/async copy of a servers disk, usually used for DR purposes, so if a production site was lost, the data would be upto data at another site (The emc version of dataguard/standby)

Priner issues .. trouble shooting

2011-06-10T19:56:00.000-07:00

#cd /etc/lp/interface

#ll|grep -i printname

#lpstat -vprintname (printer details)

#lpstat -oprintname (printer queue status)

#lpstat -pprintname (printer status)

#w
#cd

#telnet ip portno

#echo "TEST PRINT"|lp -d printname (sending a test print)

#echo "TEST PRINT"|lp -d printname

#lpstat -ojprintname (cheking weather it got fired from the queue)

LP printer Creation:

lpadmin -p -orm -orp -mrmodel -v/dev/null -orc -ocmrcmodel -osmrsmodel

lpadmin -p143_zb1 -ormAUABGN-PRN2 -orp143_zb1 -mrmodel -v/dev/null -orc -ocmrcmodel -osmrsmodel

Some useful commands.

2011-04-25T21:26:00.001-07:00

lsof is a command meaning "list open files", which is used in many Unix-like
systems to report a list of all open files and the processes that opened them

Dmidecode reports information about your system's hardware as described in your
system BIOS according to the SMBIOS/DMI standard.(Linux)

Memory & Cpu utilization :

Top (linux)

Glance(unix)

UNIX95=

swapinfo -tm

cat /proc/meminfo

free -tml (t-total,m-megabites,l-diff b/w low high)

File system utilization:

du -sk * (individually)

du -sk .(collectively)

Timex : we know time taken by different users to run a command.

Unix Nohup: Run a Command or Shell-Script Even after You Logout

When you execute a Unix job in the background ( using &, bg command), and logout from the session, your process will get killed. You can avoid this using several methods — executing the job with nohup, or making it as batch job using at, batch or cron command.

This quick tip is for beginners. If you’ve been using nohup for a while, leave us a comment and tell us under what situations you use nohup.

In this quick tip, let us review how to make your process running even after you logout, using nohup.

Nohup stands for no hang up, which can be executed as shown below.

nohup syntax:

# nohup command-with-options &

Nohup is very helpful when you have to execute a shell-script or command that take a long time to finish. In that case, you don’t want to be connected to the shell and waiting for the command to complete. Instead, execute it with nohup, exit the shell and continue with your other work.

Explanation about nohup.out file

By default, the standard output will be redirected to nohup.out file in the current directory. And the standard error will be redirected to stdout, thus it will also go to nohup.out. So, your nohup.out will contain both standard output and error messages from the script that you’ve executed using nohup command.

Instead of using nohup.out, you can also redirect the output to a file using the normal shell redirections.

Example: Printing lines to both standard output & standard error

while(true)
do
echo "standard output"
echo "standard error" 1>&2
sleep 1;
done

Execute the script without redirection

$ nohup sh custom-script.sh &
[1] 12034
$ nohup: ignoring input and appending output to `nohup.out'

$ tail -f nohup.out
standard output
standard error
standard output
standard error
..

Execute the script with redirection

$ nohup sh custom-script.sh > custom-out.log &
[1] 11069
$ nohup: ignoring input and redirecting stderr to stdout

$ tail -f custom-out.log
standard output
standard error
standard output
standard error
..

If you log-out of the shell and login again, you’ll still see the custom-script.sh running in the background.

$ ps aux | grep sathiya
sathiya  12034  0.0  0.1   4912  1080 pts/2    S    14:10   0:00 sh custom

nice - run a program with modified scheduling priority

Run COMMAND with an adjusted scheduling priority. With no COMMAND, print the current scheduling priority. ADJUST is 10 by default. Range goes from -20 (highest priority) to 19 (lowest).

-n, --adjustment=ADJUST: increment priority by ADJUST first

vgreduce -t ( This will run vgreduce in test mode)

buffer I/O error main reason is difference in I/O timings with storage lun.

[root@d scsi_device]# cat /sys/block/sdab/device/timeout

30

[root@d scsi_device]#

https://access.redhat.com/knowledge/solutions/29737

Aix commands to check kernel parameters

lsattr -E -l sys0

topas

startsrc -s sshd

Sed command to extract data b/w two words in a file

sed -n '/langham/,/langport/p' linux_workout

Mount error

mount: special device does not exist

(re activate the vg ) or check vg activation status

mounting linux drives on windows

2010-01-21T01:01:00.000-08:00

Ext2 IFS is used to mount linux drives on windows.

you can download the software from...

http://www.fs-driver.org/

mounting windows drives on linux

2009-12-10T05:22:00.001-08:00

We can mount windows drives on linux by using NTFS-3g(Linux -NTFS).
The goals of the Linux-NTFS project are to develop reliable and full feature access to NTFS by the Linux kernel driver, and by a user space filesystem (ntfsmount), and to provide a wide collection of NTFS utilities (ntfsprogs) and a developer's library (libntfs) for other GPLed programs. We have achieved already a lot, with high quality results.

How to access NTFS from Linux
Choose one of the following three options:

1) Linux has an integrated kernel driver. It allows reading of files, and rewriting existing files. It does not support creation of new files or deletion of existing files. .

2) ntfsprogs includes an improved driver, ntfsmount, which provides the same functionality as the kernel driver. Additionally it also supports basic cases of directory, symlink, device and FIFO file creation, deletion and renaming. Note: That doesn't mean it always succeeds, it is still experimental and might just as well refuse to complete an operation in order to prevent corruption. See the ntfsmount page for more details.

The beta version of the ntfs-3g driver can be downloaded from http://www.ntfs-3g.org

partitioning hardisk

2009-12-10T05:21:00.000-08:00

As outlined in the General Information section, the most common way to install Linux is to allocate a part of your hard disk for Linux. Most computers come with one hard disk, and that hard disk is usually setup to have just one partition which uses all of the space on the hard disk. If this is the case with your computer, then you will need to either add a new hard disk for Linux, or shrink your existing partition to make space for Linux.

Each partition not only creates a separate independent space on the hard disk but it also associates a method of reading and writing information to the drive, the format of the drive. Linux has a number of different formats it can use for sections of the hard disk, the most popular being ext2 and ext3 (others include reiserfs, xfs and jfs). Normally you will not have to worry much about the formats of Linux partitions, the installation program will make appropriate suggestions. One other type of partition format for Linux which is worthy of mention is swap. A swap partition is used to effectively extend your memory onto the hard disk, so if your computer wants to use more memory then it has, it will "swap" information in memory which it doesn't need at the time onto the hard disk. It is possible to use a large file on a normal partition for swap however this is much slower. Unless you measure your memory in Gigabytes, you should probably use a swap partition at least the size of your memory, and if you have less then 256Megabytes of ram then you may want a partition 2 or 3 times it.

If you are in the common situation of having to shrink the only Windows partition on your hard disk, the first thing to be aware of is that your access to the information on the Windows partition will depend on its format. There are two main types of partition formats for Windows, FAT and NTFS. Generally computers with the Windows 95/98/ME systems will have FAT partitions and Windows NT/2000/XP will have NTFS partitions, though the NT/2000/XP family can also use FAT.

The critical difference between FAT and NTFS as far as Linux is concerned, is that while reading information from either system is perfectly safe under Linux, writing information to an NTFS partition is currently regarded as potentially unsafe so you wouldn't be able to edit these files from Linux and access the changes directly under Windows. Linux is perfectly reliable sharing FAT partitions with other operating systems (if your feeling lost, perhaps telling you that when you format a floppy you are actually making a FAT filesystem on it will help put things in perspective). Windows has no native method of reading Linux formatted partitions, but the Free explore2fs program allows you to read and copy information from ext2 and ext3 Linux partitions while you are running Windows. There is now also a file-system driver from the same source called ext2ifs which allows your ext2 and ext3 partitions to appear as extra drives in Windows NT4/2000/XP (still read only).

There are numerous methods for shrinking Windows partitions to make space for Linux (and I would recommend simply making the space and using the installer to create the partitions and format them). No matter what method you use to do this, you should backup all your data before you begin, in fact you should always keep backups of all your important information as a hard disk could fail at any time. Another tip is to defragment your drive in windows before you begin which makes it much easier for the software which has to do the shrinking. The tried and true method for shrinking a partition is a commercial program called Partition Magic ($69.95 as of Sept 2004). You can also do this with Free software such as parted (or the graphical front-end QTparted) or often as part of the installer itself. Check the installation documentation for the system you plan on installing to see if it's now supports resizing/shrinking ntfs partitions.

Whatever scenario you start in, when you begin to install Linux you need to know where you have space to put it. It may be a new hard disk or free space on an existing hard disk. For a modern desktop Linux system you would want to allocate an absolute minimum of 2GB of hard disk space, 5GB would be far better and if you have plenty of space (or if you plan to install lots of large pieces of software, perhaps games) 10GB+ is perfectly reasonable. If you have enough free space the installation program may suggest creating more than one Linux partition, if so it is well worthwhile creating a separate partition for your files, the /home partition. Amongst other things you can reinstall your system or install a new system without having to make an additional backup of your files (remember again you do always keep backups of everything important).

hierarchy of file system

2009-12-10T05:19:00.000-08:00

< / >

The root directory. The starting point of your directory structure. This is where the Linux system begins. Every other file and directory on your system is under the root directory. Usually the root directory contains only subdirectories, so it's a bad idea to store single files directly under root.

Don't confuse the root directory with the root user account, root password (which obviously is the root user's password) or root user's home directory.

< /boot >

As the name suggests, this is the place where Linux keeps information that it needs when booting up. For example, this is where the Linux kernel is kept. If you list the contents of /boot, you'll see a file called vmlinuz - that's the kernel.

< /etc >

The configuration files for the Linux system. Most of these files are text files and can be edited by hand. Some interesting stuff in this directory:

/etc/inittab

A text file that describes what processes are started at system bootup and during normal operation. For example, here you can determine if you want the X Window System to start automatically at bootup, and configure what happens when a user presses Ctrl+Alt+Del.

/etc/fstab

This file contains descriptive information about the various file systems and their mount points, like floppies, cdroms, and so on.

/etc/passwd

A file that contains various pieces of information for each user account. This is where the users are defined.

< /bin, /usr/bin >

These two directories contain a lot of programs (binaries, hence the directory's name) for the system. The /bin directory contains the most important programs that the system needs to operate, such as the shells, ls, grep, and other essential things. /usr/bin in turn contains applications for the system's users. However, in some cases it really doesn't make much difference if you put the program in /bin or /usr/bin.

< /sbin, /usr/sbin >

Most system administration programs are stored in these directories. In many cases you must run these programs as the root user.

< /usr >

This directory contains user applications and a variety of other things for them, like their source codes, and pictures, docs, or config files they use. /usr is the largest directory on a Linux system, and some people like to have it on a separate partition. Some interesting stuff in /usr:

/usr/doc

Documentation for the user apps, in many file formats.

/usr/share

Config files and graphics for many user apps.

/usr/src

Source code files for the system's software, including the Linux kernel.

/usr/include

Header files for the C compiler. The header files define structures and constants that are needed for building most standard programs. A subdirectory under /usr/include contains headers for the C++ compiler.

/usr/X11R6

The X Window System and things for it. The subdirectories under /usr/X11R6 may contain some X binaries themselves, as well as documentation, header files, config files, icons, sounds, and other things related to the graphical programs.

< /usr/local >

This is where you install apps and other files for use on the local machine. If your machine is a part of a network, the /usr directory may physically be on another machine and can be shared by many networked Linux workstations. On this kind of a network, the /usr/local directory contains only stuff that is not supposed to be used on many machines and is intended for use at the local machine only.

Most likely your machine isn't a part of a network like this, but it doesn't mean that /usr/local is useless. If you find interesting apps that aren't officially a part of your distro, you should install them in /usr/local. For example, if the app would normally go to /usr/bin but it isn't a part of your distro, you should install it in /usr/local/bin instead. When you keep your own programs away from the programs that are included in your distro, you'll avoid confusion and keep things nice and clean.

< /lib >

The shared libraries for programs that are dynamically linked. The shared libraries are similar to DLL's on Winblows.

< /home >

This is where users keep their personal files. Every user has their own directory under /home, and usually it's the only place where normal users are allowed to write files. You can configure a Linux system so that normal users can't even list the contents of other users' home directories. This means that if your family members have their own user accounts on your Linux system, they won't see all the w4r3z you keep in your home directory. ;-)

< /root >

The superuser's (root's) home directory. Don't confuse this with the root directory (/) of a Linux system.

< /var >

This directory contains variable data that changes constantly when the system is running. Some interesting subdirectories:

/var/log

A directory that contains system log files. They're updated when the system runs, and checking them out can give you valuable info about the health of your system. If something in your system suddenly goes wrong, the log files may contain some info about the situation.

/var/mail

Incoming and outgoing mail is stored in this directory.

/var/spool

This directory holds files that are queued for some process, like printing.

< /tmp >

Programs can write their temporary files here.

< /dev >

The devices that are available to a Linux system. Remember that in Linux, devices are treated like files and you can read and write devices like they were files. For example, /dev/fd0 is your first floppy drive, /dev/cdrom is your CD drive, /dev/hda is the first IDE hard drive, and so on. All the devices that a Linux kernel can understand are located under /dev, and that's why it contains hundreds of entries.

< /mnt >

This directory is used for mount points. The different physical storage devices (like the hard disk drives, floppies, CD-ROM's) must be attached to some directory in the file system tree before they can be accessed. This attaching is called mounting, and the directory where the device is attached is called the mount point.

The /mnt directory contains mount points for different devices, like /mnt/floppy for the floppy drive, /mnt/cdrom for the CD-ROM, and so on. However, you're not forced to use the /mnt directory for this purpose, you can use whatever directory you wish. Actually in some distros, like Debian and SuSE, the default is to use /floppy and /cdrom as mount points instead of directories under /mnt.

< /proc >

This is a special directory. Well, actually /proc is just a virtual directory, because it doesn't exist at all! It contains some info about the kernel itself. There's a bunch of numbered entries that correspond to all processes running on the system, and there are also named entries that permit access to the current configuration of the system. Many of these entries can be viewed.

< /lost+found >

Here Linux keeps the files that it restores after a system crash or when a partition hasn't been unmounted before a system shutdown. This way you can recover files that would otherwise have been lost.

dual booting linux and windows on same machine

2009-12-10T05:17:00.001-08:00

Windows and Linux can live comfortably on the same the same machine, even the same harddrive. The choice of operating systems can be made at the boot-up sequence when you thro the power switch. This configuration is known as the "dual-boot" configuration. This is how most linux users start off. Unless you're a BOFH of course *grin*.
FAT32 Support Requirements
To have access to your Win partition from Linux (file sharing between Linux and Win), which is useful, think of all those MP3s... you will also need a version 2.0.34 of the Linux kernel or higher. Below is a list of recent Linux distros and the kernel build versions (2.0.34 or higher!) that support FAT32.

If your kernel version doesn't support Fat32 you will have to upgrade the kernel. I'm not too hot on kernel upgrades, so I'm not going to say too much on that. As ever RTFM!

Distributions with FAT32 support (kernel 2.0.34 or higher) Distribution:
        Earliest Version with FAT32 Support
Red Hat
        Version 5.1 (with kernel 2.0.34)

Red Hat
        Version 6.0 (with kernel 2.0.36)

SuSE
        Version 5.3 (with kernel 2.0.35)

SuSE
        Version 6.0 (with kernel 2.0.36)

Debian GNU/Linux
        Version 2.0 (with kernel 2.0.34)