Frequently Asked Unix Operating System Questions

 

WARNING:  THE QUESTIONS AND ANSWERS IN THIS SECTION ARE DESIGNED FOR SYSTEM ADMINISTRATORS OR ADVANCED USERS.  THEY ARE NOT DESIGNED FOR THE EVERYDAY USER.

How do I access the UNIX Prompt?
What checks should be done on the UNIX system?
How do I change a user's password?
How do I change the system time?
How do I reboot or shutdown the UNIX Server?
How do I check the disk space on the UNIX server?
How do I set up a new user?
How do I check for Zombies Processes?
How do I verify that my backup was successful?
 

 

 

 


 

 



How do I access the UNIX prompt?

This is how you log on with access to the UNIX prompt. At the login prompt type in root and press enter. Then enter the password for root, if you do not know this please contact phone support for assistance, and 

press enter. See the below example:

Login: root

Password: _______________

Logging on as root normally gets you directly to the UNIX prompt.  In some cases it 

may display the SYSTEM MANAGER menu (see below).  If it does take option 6… Unix 

Shell to get to the prompt.

The appearance of the unix prompt can vary by site and unix revision but it normally 

looks something similar to one of the examples below:

 #

/>                 

city:/>

  

To exit from the unix prompt type

 exit

 or

 ctrl D

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What checks should be done on the UNIX system?

We have provided in this check list that a system administrator or the advanced user can use to help maintain the UNIX system.

System Administrator Checklist

Daily

 Check the system printer for backup success or failure messages

 Check the system printer for cleanup script disk space information

 Make sure the backup tapes are stored properly and logged in the backup log book

 Check the master console for system error messages

 Check the /usr/adm/messages file for system error messages

 Login with access to the UNIX prompt and type

tail –100 /usr/adm/messages | pg

This will allow you to view (a page at a time) the system error log

 

Make sure the system users log off daily

 Login with access to the unix prompt and type who

This will display a list of users logged into the system and the date/time they 

logged on.

  Monthly

 1        Shutdown the server, (power off is optional), and re-boot.

 2        Clean the tape drive

 3        Do a monthly backup and store it off site

 4    Review and update your hardware maintenance agreements

 5  ___________________________________________________________________

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How do I change a user’s password?

You would need access to the Unix prompt (see how do I access the 

unix prompt? ) If you do not have access, you must contact your 

administrator or phone support to have your password changed.

Once you have logged in with access to the unix prompt

Type passwd john  (where john is the users password you need to change) and 

press enter.

Once you press enter the below information will display.   

                

             (Note: when you enter the password, it will not show on the screen.)                                                                                       

Once you have changed the password you will return to the unix prompt. Type exit  

at the prompt and the system will log you off  and you can then login as normal.

 


 




How do I change the system time?

To change the system date / time you must be able to login with access to the 

unix prompt (see how do I access the unix prompt?) and type:

asktime  and press enter 

Once you press enter the current time of the system will display and it will also give 

you an opportunity to change it as shown below:                                            

Current System Time is Wed Apr 28 10:02:27 CDT 2004  

Enter new time ([[CC]YYMMDD]hhmm[.ss]): 20040428100430

Wed Apr 28 10:04:30 CDT 2004

 

Once you have changed the time you will return to the unix prompt. Type exit at the 

prompt and the system will log you off and you can then login as normal.

Note: When you re-boot your Unix Server during the boot up process it will come to a 

point where it displays the current date/time and will allow you to change it there as 

well.

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How do I reboot or shutdown the UNIX Server?

Using the Init command to “init 0” shutdown or “init 6” shutdown/reboot

the server

The unix init command can be used to shutdown the server from any workstation or 

terminal or even from a dialup modem connection or telnet connection to the server.

The Zortec  “Shutdown the System” menu option that you normally use will only allow 

the system to be shutdown from the console.  In extreme cases (for example) where 

the console terminal is not working or the system is having hardware or operating 

system problems or you simply would rather shutdown or reboot the system from 

another workstation the init command can be used.

To issue the shutdown command simply login with access to the unix prompt (see 

how do I access the UNIX prompt? ) and type:

init 0       (to shutdown) and press enter

Note:  init 0 (and that’s the number zero) will take the system down ASAP.  The init 0 command will terminate all user processes and print request and take the system down  

to the “Safe to Power Off” message on the console.

To issue the shutdown command simply login with access to the unix prompt (see how 

do I access the UNIX prompt? ) and type

init 6       (to shutdown & reboot) and press enter

Note:  init 6  will take the system down ASAP (just like init 0 above) and will then boot

the system back up.  It normally takes around 2 or 3 minutes for the init 6 command to 

complete and when it’s finished the console and all workstations will be sent the Login prompt.  At that point the system is ready for normal use.

The init 6 command can be issued from a dialup or telnet connection as mentioned 

above and one benefit to this is that a system administrator can elect to reboot the 

unix server from a dialup or telnet connection from a home computer or any remote 

location. This allows for rebooting the unix server after hours or on weekends when 

users are not running applications on the server.

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How do I check the disk space on the UNIX server?

Disk space information is printed each night on your system default printer each time the cleanup script runs.  The cleanup script should run each night Mon – Fri at 23:00 hours. You can simply read the information off that printout or use the steps below to check the space any time you need to.

Login and get to the UNIX prompt (see how do I access the UNIX 

prompt? ), and type:

df -v   and press enter. The below information will display.                                       

Mount Dir  Filesystem              blocks      used      free   %used

/          /dev/root              1126402    732530    393872    66% 

/stand     /dev/boot                30722     18492     12230    61% 

/thms      /dev/files_progs       6542972   1374890   5168082    22%

If your root filesystem shows more than 80% (used or capacity) then you are running low on root space.  Running low on root space can affect your system performance and if it gets full ( 99 or 100% ) the system will stop functioning. When a Unix Server gets dangerously low on root filesystem space you will normally experience user login problems and failed print request.

(Sites without the Zortec Utility Billing Application running NBACK backup to disk)

If your files_progs filesystem shows more than 90% (used or capacity) you are running low on (Zortec application programs and files space).

(Sites with the Zortec Utility Billing Application running NBACK backup to disk)

If your files_progs filesystem shows more than 70% (used or capacity) you are running low on (Zortec application programs and files space).

If you find your filesystems have exceeded the (used or capacity) % mentioned above 

call or email the Phone Support for help. In most cases we can clean up the filesystem manually and get enough space back for you to continue normal operations.

Note:  The cleanup script should run each night on your system.  It searches the file systems for junk files, unnecessary log files and print files in the tmp directory.  It removes these files to help keep the space from growing as a result of daily operations. 

If the cleanup script stops running (and it does occasionally) your root filesystem will soon run out of space.  Check the system printer each morning for the cleanup script printout.  If you don’t get a cleanup report on your system default printer the cleanup script may not be running.  Call or email the Phone Support for help.

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How do I set up a new user?

We will explain how to do this in a SCO_SV Systems.

Login at the console with access to the unix prompt and type (see How do

I access the unix prompt? )

Scoadmin and press enter. The scoadmin screen will display.

Once the screen has displayed choose the option Account Manager and press enter from the Account manager menu arrow over to Users and press enter from the Users menu chose Add new user and press enter. The screen below will display.

Login field: enter the new user’s name making sure to use small letters (no capital letters should be use)

Comment field: nothing is required so you can leave blank.

Password field: make sure there is a * in the “set password now” field

Login Shell field: accept the default by pressing enter.

Networked Via field: leave as is and press enter

Home Directory field:  accept the default by pressing enter

Login Group field: accept the default by pressing enter.

At this point you will be at the bottom of the screen and OK will be highlighted press enter.

 

Once you press OK the screen below will display.

Make sure that there is a * in the “Enter a new password” field and press enter.

Enter Password field:   enter what will be the password for the new user and press enter.

Confirm Password field: enter the same password as you did in “Enter Password” field and press enter.

Force Password Change at Next Login field: make sure it is blank and press enter.

At this point you will be at the bottom of the screen and OK will be highlighted press enter.

 

To exit from the account manager menu arrow over to “host” and press enter then choose the “exit” option and press enter.

Once you have pressed enter the main scoadmin menu will appear and from the scoadmin main menu using you tab key, tab up to “file” option and press enter then choose the “exit” option and press enter.

This takes you back to the UNIX prompt. 

That completes the steps necessary to add a new login account “user” to your UNIX system.

 

Note: Additional Steps necessary to get a new user working in Zortec Applications.

To give the new user access to the Zortec Applications requires a few more steps.

You must create a System Wide User Profile and Defaults for the new user.

Helpful Hints:  Inquire on an existing user and create the new user from that example.  

Use the duplicate function to copy from an existing user to the new one. You must also create a User Profile and Defaults for each application the user will have access to (Payroll, General Ledger, Utility Billing, etc).  Inquire on an existing user and create or duplicate the new one.

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How do I check for Zombies Processes?

Zombie processes are processes which are running amuck on the system and accumulating lots of processor time. They are usually the result of incorrectly terminating a user’s windows session with the UNIX system.   

To avoid this PC users should always exit from the Zortec applications and log off the UNIX system before they shutdown their Term connection or shutdown the PC workstation.

The result of Zombie Processes is a serious reduction in system speed!

Any process which has accumulated more than 20:00 minutes of processor time should be investigated and possibly terminated. If your system is running slow, check for zombie processes. If you find some potential zombies, check with the user(s) responsible to verify their activity. If they have been running some processor heavy jobs like updating a payroll or billing the high processor time could be valid. Have them log off the system from every workstation that they are logged in on and then you should check for Zombie Processes again. If the processes still show up for that user, after they logged off you know they are zombies.

To check for zombie processes logon with access to the UNIX prompt (see How do I access the unix prompt? ) and type ps -ef | grep Z and press enter.

Once you have press enter you will see the below information:  

 melindaw 26785 26784 2 Aug 04   pts/9  355:28 Z XX9100

   root  2345  2179 7  07:45:48 pts/0  0:00   grep Z

melindaw 26680 26679 1 Aug 04   pts/3  356:53 Z XX9100

melindaw 26732 26731 2 Aug 04   pts/6  356:05 Z XX9100

   root  28434 28433 7 08:58:57 pts/16 0:12   Z XX9100

melindaw 26219 26218 1 Aug 04   pts/21 359:00 Z XX9100

   root  2237  2236 7  07:27:21 pts/1  0:04   Z XX9100

joy 2286 2285  6       07:40:47 pts/4  0:06   Z XX9100

   root  2340  2339 7  07:43:50 pts/5  0:04   Z XX9100

 

The list above shows 4 potential zombie processes: 26785 26680 26732 and 26219

Have the user(s) in question log off at the terminals in question and then do another 

ps -ef | grep Z to see if the suspected zombies still exist. If they do then kill them off the system or shutdown and re-boot the system to clear them.

If you want kill them off use the example below:

kill –9 26785 26732 26680 26219 and press enter

Warning:  Be very careful when using the kill command. If you accidentally kill the 

wrong process id number you could shutdown the system or stop some other important

operating system process.

 

 If you simply shutdown the system and re-boot it will stop all the processes 

(including zombies) and restart normally.  It’s one easy and safe way to make sure 

that the system processes get back to normal.  The system should be shutdown and re-booted on a Monthly basis but any time you notice the system slowing down when 

there are no heavy processes running (like payrolls, billings or system backups) it’s a 

good idea to shutdown and re-boot.

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How do I verify that my backup was successful?

To verify backup success do the following:

Logging your backups

Keep a log book and record each backup including information like – Backup set name – Number of tapes used – Start and completion date/time – Initials of the employee who performed the backup.

This information can be very important if you do have to restore files as of a specific 

point in time to resolve a problem.

Verifying backup success

Check the system default printer each morning for backup success or failure messages.  Report any failures to Zortec Support.

Storing a monthly set off site

If a true disaster strikes your site (fire, flood, tornado, etc…) this could be your only 

hope of getting your system back up and running with your data.

Purchasing new tapes yearly

Backup tapes do not last forever!  Budget for and purchase new tape sets yearly.

Clean your tape drive monthly

It’s a simple procedure that will help guarantee backup success and extend the life 

of your tape drive and backup tapes.  Failure to clean your tape drive will result in soft 

errors, hard errors and backup failures.

Make sure you have enough backup set generations

(Below is an example of what we recommend)

Set A – Monday, Tuesday, Wednesday, Thursday, Friday    (alternate between set)

Set B – Monday, Tuesday, Wednesday, Thursday, Friday    (A, B & C weekly      )

Set C – Monday, Tuesday, Wednesday, Thursday, Friday

Monthly Set 1, Set 2, Set 3        (alternate between monthly)

                                                        (Set 1, 2, & 3 on the last)

                                                        (Day of each month.  )

 

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