Sun Solaris Administration Interview Questions and Answers

Solaris is a proprietary Unix operating system originally developed by Sun Microsystems. It superseded the company’s earlier SunOS in 1993. In 2010, after the Sun acquisition by Oracle, it was renamed Oracle Solaris.Solaris is known for its scalability, especially on SPARC systems, and for originating many innovative features such as DTrace, ZFS and Time Slider.Solaris supports SPARC and x86-64 workstations and servers from Oracle and other vendors. Solaris is registered as compliant with the Single UNIX Specification.

1.What Is An Alternative To The “top” Command On Solaris?

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2.Is It Possible To Create Swap In New Hard Disk Without Format ?

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“ No “ without label the drive, you can’t do anything

3.Is It Possible To Edit The Crontab Using Vi, It Is Not Recommended But It Is Possible By Editing?

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• # vi /var/spool/cron/crontabs/root
• The command to edit the crontab is #crontab -e

4.What Is Mean By Paging & Server Average Time?

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If a disk shows consistently high reads/writes along with , the percentage busy (%b) of the disks is greater than 5 percent, and the average service time  (svc_t) is greater than 30 milliseconds, then  one of the following action needs to be taken

5.Cannot Open ‘/etc/path_to_inst’” ?

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System can not find the /etc/path_to_install file. It might be missing or corrupted and needs to be rebuild.

To rebuild this file  boot the system with  -ar option :

ok>boot -ar

Press enter to select default values for the questions asked during booting and select yes to rebuild /etc/path_to_install

The /etc/path_to_inst on your system does not exist or is empty. Do you want to rebuild this file [n]? y

system will continue booting after rebuilding the file.

6.How Will You Comment Error Line In /etc/system File ?

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# Vi /etc/system

(To comment the error line in /etc/system files, we have to use *)

7.What Is Difference Between Incremental Backup And Differential Backup?

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Incremental:

Only those files will be included which have been changed since the last backup.

Differential:

Only those files will be included which have been changed since the last Full backup.

8.How Many Ufsdump Level?

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1-9 = Incremental backup of file,That have changed since the last lower level backup.

9.What Is Different Between Crontab And At Command?

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Crontab: job can be scheduled

At: Job can be a run once only

10.Difference Between Ufs And Tar Command?

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ufsdump: 

• Used for complete file system backup.
• It copies every thing from regular files in a file system to special character and block device files.
• It can work on mounted or unmounted file systems.
• Tar:
• • Used for single or multiple files backup.
  • Can’t backup special character & block device files.
  • Works only on mounted file system.

11.Syntex To Execute A Ufsdump ?

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12.To Check The Status Of The Media Inserted On The Tape Drive ?

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13.How Will You Take Ufsdump And Ufsrestore In A Sing Command Line?

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14.What Is The Physical Device To Check The 2 Nodes Connect In Cluster ?

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Physical fiber cable which is connect to the 2 nodes is called a HTEARTBEAT

15.Where Will Be The Configuration For Metadevice?

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16.Explain Raid0, Raid1, Raid3?

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RAID 0 Concatenation/Striping

RAID 1 Mirroring

RAID 5-Striped array with rotating parity.

• Concatenation: Concatenation is joining of two or more disk slices to add up the disk space. Concatenation is serial in nature i.e. sequential data operations are performed serially on first disk then second disk and so on. Due to serial nature new slices can be added up without having to take the backup of entire concatenated volume, adding slice and restoring backup.
• Striping: Spreading of data over multiple disk drives mainly to enhance the performance by distributing data in alternating chunks – 16 k interleave across the stripes. Sequential data operations are performed in parallel on all the stripes by reading/writing 16k data blocks alternatively form the disk stripes.
• Mirroring: Mirroring provides data redundancy by simultaneously writing data on to two sub mirrors of a mirrored device. A submirror can be a stripe or concatenated volume and a mirror can have three mirrors. Main concern here is that a mirror needs as much as the volume to be mirrored.
• RAID 5: RAID 5 provides data redundancy and advantage of striping and uses less space than mirroring. A RAID 5 is made up of at least three disks, which are

 striped with parity information written alternately on all the disks. In case of a single disk failure the data can be rebuild using the parity information from the remaining disks.

17.What Are The Daemons In Nis Server?

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18.What Are Processing Daemon In Nis?

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19.How To Boot The Solaris System In 64 0r 32 Bit Kernel?

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For 64 bit:

For 32 bit:

20.Which Command To Lock The User Account?

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21.What Is Difference Between Hard And Soft Mount?

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Hardmount: Normal file system mount used mainly for mounting local file systems. Once a file system is hard mounted, can use a normal filesystem untill its umount.

Soft mount: It allows automatic unmounting if the filesystem is idle for a specified timeout period. It is mainly used for network filesystems like NFS It can be configured using Autofs and the network filesystem can be soft mounted.

22.To Find The Obp Environment Variable?

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OK printenv

23.How To Find Out The Shared File System From Server And Client?

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Server :

• # share  & dfmount
• Client : # showmount –e (hostname) and dfshares
• OK printenv

24.How To Start / Stop The Nfs Server ?

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25.How To Delete “abc” Files Using Find Command ?

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26.How Do You Add The Disk Without Reboot The Server?

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27.How To Change The Hostname And Ethernet Address In Single Command ?

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28.How To Enable And Disable The Dtlogin?

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29.How To Find The Kernel Bit Version Or Architecture?

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30.How To Set Passwd Never Expire For A User?

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31.Explain Setuid, Setgid And Stickybit?

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Setuid : When setuid permission set on a executable file, user who access the file is granted access permission of the owner of the file.

setgid : Permission similar to setuid, The process is changed to owner of the file.

Stickybit : It is a special permission that protect the files within a public writable directory. Stickybit permission set the shared directory, user can create a files or directory. But only by owner of the directory can modify or delete.

32.What Is Umask?

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UMASK is a Unix environment variable, which automatically sets file permissions on newly created files.

33.What Is Default Permission Of Files And Directory?

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• file: 644
• directory: 755

34.What Is Default Permission Of /etc/passwd , /etc/shadow Files?

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• /etc/passwd:  644
• /etc/shadow: 400

35.As A User How He Can Change Is Passwd With Root Privilege.?

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Setuid to set on  /usr/bin/passwd  command

36.What Are Performance Tool Used?

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Iostat ,vmstat , prstat , sar ,netstat, top

37.Which Service Assign Port No Dynamically?

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Rpc service ( /etc/rpc)

38.What Is Nice And Renice Command Do?

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To set the high priority for the process

• -20 high priorities
• +20 low priorities

Eg:

# nice –20 oracle

39.How Will You Restart The Inetd Process?

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40.Tell Me The Port For Telnet, Ftp,nis,ssh,nfs?

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41.In Which File Port No’s Are Defined?

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# /etc/service

42.If Telnet Not Working, What Are The Thing To Be Checked?

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Ping test, service enable or not in (/etc/inetd.conf), NIS problem

If telnet is not working, first of all you will not be get connected, login through console access and then find out with ps -ef | grep telnetd or Kill -1

43.How Do You Check The Run Level?

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44.How Do You Check The No Of User Logged Into The System?

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45.How Will You Check The Process For Particular User?

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46.How To Check The No Of The Processor Available?

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47.How To Bring The Process To Offline Or Online?

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• # psradm –f (no of the process)
• # psradm –a –n ( no of the process)

48.How To Find The Boot Path In Solaris?

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49.What Is The Difference Between Dsk And Rdsk?

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DSK:

Block level devices

RDSK:

Raw level device or character level device

50.Explain About Admin Command?

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Local Kerberos services can be managed by administering policies, key tabs and principles by managing the admin command. Admin.local is used to master KDC and it does not require any authentication. On the server login information is passed through a secured server. It checks the principle name by the value of the user environment variable.

51.Explain About The Command Prof_attr?

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This forms the RBAC profile database. It displays the relationship between among the profiles in the database. It also gives authorizations between navigation for those files. One of the samples is Solaris.admin.fsmgr.read.solaris.admin.serialmgr.read.

52.Explain The Differences Between Setting Files Using Octal Codes And Symbolic Codes?

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The main difference between setting files using octal and symbolic code files is symbolic codes are relative whereas octal codes are numeric codes. These settings will remain unless you change the settings explicitly by using symbolic codes. If group execute access gets executed it automatically removes write access permission.

53.What Is The Best Solution To Avoid Large Number Of Groups?

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The best solution for not creating large number of groups lies with the system administrator. It is best to use structural group membership which reflects organizational divisions. To manage file access a system admin can use access control lists.

54.How Can You Determine Whether A File Is Setuid?

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The easiest way to determine whether a file is setuid or not by checking for files which are owned by the root and after checking for files that are owned by root you can check for s flag files assigned to the user permissions. In the permission table the first s refers to setuid root.

55.Explain About Sticky Bit Permissions?

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This command helps the network administrator to relax a bit. This command will not allow the deletion of the common files present in the common area. This command helps the users by not allowing them to rewrite on other files. Certain permissions can be set which will restrict users to delete files created by them.

56.Explain About The Command Ls?

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Ls command gives a way to the main directory and also gives access permissions for files in Solaris. It displays and prints user and group ownerships, file access permissions, filename and files size and creation date.

57.Explain About The Limitations Present In Sudo?

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There are some limitations for sudo which makes RBAC popular they are

• It is not possible to assign a user to work on specific file or profile.
• It is also not possible to assign a user to work on a specific command.
• By using shell commands and certain functions it is possible to have some restrictions on a user but it would consume time for a larger setup.

58.What Is Sudo?

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Sudo maintains database of all the privileges assigned to a user name. These privileges can be identified by different commands present in the database. This feature helps a user to format a disk but the root system cannot be changed.

59.What Are The Different Ways To Execute Profiles?

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Profiles can be executed in many different ways some of them are

• Pfexec executes a single command in profile.
• With some restrictions pfsh and pfcsh can be executed.
• By directly logging into the account using su.

60.What Is Solaris Roles?

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RBAC implementation depends upon the role specified in the administrator profiles. Roles are implemented according to the profile. Also access to certain files and configuration can be assigned by the user profile. It also allows RBAC to differentiate high technical knowledge roles from low ones.

61.What Is Rbac?

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RBAC is introduced into Solaris for managing specific tasks. These specific tasks are based and defined in the administrator profile. It is based on the standard developed by NIST. RBAC is a very important tool for performing multiple tasks. It also separates tasks which require high technical knowledge 

62.Describe About Logical Domains And Its Functions?

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LDOMS system administrator center provides resources and links to developers who are trying to install Ldoms technology. It gives you flexibility to group system resources and discrete systems within a computer system physically. It allows you to group system resources physically within its own operating system, identity and resources.

Solaris UNIX version runs on Intel, AMD and SPARC platforms. It has migrated from solely a SPARC platform to include other platforms from leading companies. It provides interoperability across various technologies such as developer products, desktop applications, data center, etc.

63.Explain About Solaris?

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Solaris is a UNIX based operating system which is available for free. It supports workstations and servers from sun. It is widely recognized for its scalability. This product is almost supported by many server vendors. It is the famous successor to sun operating systems.

64.Set The Display Automatically For The Current New User?

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export DISPLAY=`eval ‘who am i | cut -d”(” -f2 | cut -d”)” -f1’`Here in above command, see single quote, double quote, grave accent is used. Observe carefully.

65.Display The Processes, Which Are Running Under Your Username?

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Ps .aef | grep Mahesh vjHere, Mahesh vj is the username.

66.List Some Hot Keys For Bash Shell?

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Ctrl+l . Clears the Screen. Ctrl+r . Does a search in previously given commands in shell. Ctrl+l – Clears the typing before the hotkey. Ctrl+a . Places cursor at the beginning of the command at shell. Ctrl+e . Places cursor at the end of the command at shell. Ctrl+d . Kills the shell. Ctrl+z . Places the currently running process into background.

67.How To Know The Date And Time For . When Script Is Executed ?

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Add the following script line in shell script. Eval echo “Script is executed at `date`” >> time info.inf Here, .timeinfo.inf. Contains date & time details ie. When script is executed and history related to execution.

68.What File Do You Put The Umask Setting In?

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The UMASK value for Bourne and korn shell users can be modified system wide by editing the “umask” entry in the “/etc/profile” file. To change the default UMASK for the C shell, modify the UMASK variable in “/etc/default/login” file.

69.Which Nfs Daemons Are Found On The Nfs Server?

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• Nfsd
• Mounted
• Locked
• Statd
• Nfs Lockd

These five daemons will be in NFS server.

Statd and locked will be in NFS client too.

70.What is the command to do an interactive boot from the ok prompt?

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After Power on, press, STOP+A at the ok prompt type, ok>boot –a

71.How can u check parameters in ok boot prompt?

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ok>printenv

72.How to Formating a disk in solaris?

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add the disk , run devfsadm command

then format command > select disk , enter the required details for formating

create a new partition table using the format command.

then create a new file system on it using

73.How do we know how many LAN cards we have in server?

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Just Type in the following command at prompt#ifconfig -a.That shall give the LAN Cards as well as total Physical and Logical IP Addresses dmesg – It displays all configured items on systems.

74.Which command display diagnostics in ok boot prompt?

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Diagnostic Test Commands

1) watch-net   % To check network connections

2) test net % To test network conection

3) probe-scsi  % To find the devices attached to SCSI BUS.

75.What is the difference between /dev/dsk and /dev/rdsk ?

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In Solaris whenever we create a new slice using format command a raw physical slice or a Raw Device will be created which is addressed as /dev/rdsk/c#d#s# where # is the number for slice.

After formatting it with newfs command the slice will be addressed as /dev/dsk/c#d#s# which can now be used for mounting.

/dev actually contains logical device names which are links (Shortcuts in windows terminology) to actual physical devices in /devices directory.

76.What is the use of Growfs utility in solaris

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Growfs is generally used for expanding storage capacity of volume with existing data.

77.What are LDOMS?

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Sun Logical Domains or LDoms is a full virtual machine that runs an independent operating system instance and contains virtualized CPU, memory, storage, console, and cryptographic devices. This technology allows you to allocate a system resources into logical groupings and create multiple, discrete systems, each with their own operating system, resources, and identity within a single computer system.

We can run a variety of applications software in different logical domains and keep them independent of performance and security purposes. The LDoms environment can help to achieve greater resource usage, better scaling, and increased security and isolation.

78.What command will display the VTOC for disk c0t0d0s0?

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prtvtoc /dev/rdsk/c0t0d0s0

79.What is the difference between container and zones?

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Zones:

A zone is a virtual operating system abstraction that provides a secured environment where applications run.The applications are protected from each other to provide software fault isolation.

Container:

zone + resource management The ability to control resource usage for processes,task and zones.Resources can be CPU level,RAM,virtual memory,Kernel level tables etc.

80.What is the use of ufsdump command  in solaris

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To take backup of a filesystem.

81.What file controls system wide password aging?

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/etc/shadow file contain the user password information,/etc/default/passwd whith the help of this file we can set the password parameters

82.What does fmthard do?

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fmthard is tools for copy VTOC (Virtual table of contents)one Hard drive to other Hard  drive

83.How can i disable STOP+A utility on SUN machines, which brings system into OK> prompt?

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There are several ways to disable “STOP-A”

(1)Edit the /etc/default/kbd file

(2)Use the “kbd -a disable” command

(3) Edit /etc/system file

84.What is sticky bit in Solaris?

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Sticky Bit is a permission bit that protects the files with in a Directory. If the directory has sticky bit set, a file can be deleted by the owner of the file, the owner of the directory or root. This Prevents a user from deleting other users files from public directories . The sticky bit is displayed as the letter t in the execute field for ‘others’.

85.What is ndd?

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ndd utility is used to examine and set kernel parameters, namely the TCP/IP drivers.

To see which parameters are available for a particular driver, use the following ndd command:

86.Setting parameters

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ndd -set /dev/hme link_speed 1 ;

ndd /dev/hme link_speed ( to view the O/P)

eg To see which parameters are available  ARP, IP, ICMP, and TCP drivers

87.What is an alternative to the ?top? command on Solaris?

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prstat

88.What is /etc/system

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Alternative for /etc/sysctl.conf ( linux)

The /etc/system file provides a static mechanism for adjusting the values of kernel variables. Values specified in this file are read at boot time and are applied. Any changes made to the file are not applied to the operating system until the system is rebooted.

89.How can we find RAM size in solaris server ?

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In Solaris 10 you can find the RAM Size using sdtwsinfo command. This command gives complete Workstation Configuration Information in a pop up window.

90.What does the pkgadd command do?

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To install packages in solaris

Adding package from CDROM

eg # pkgadd -d /cdrom/cdrom0/Solaris_9/Product SUNWgtar

Adding packages to spool directory and then install them

pkgadd -d /cdrom/cdrom0/Solaris_9/Product -s /var/spool/pkg SUNWgtar

91.What is jumpstart and what are the various steps used in it.

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Jumpstart is used to manage operating system installation in many Information technology environments (corporate and otherwise) where Solaris operating system computers are widely used.

It can provide easier installation (minor setup on central server, then one command on an installation “client” system to start it installing). It also allows completely consistent system installation on many systems over time – each install can have exactly the same system configuration and software tools../

1. 1. Preparing for a jumpstart server (making export dir)
2. 2. Setting up an Install server
3. 3. Setting up a boot serve
4. 4. Setting up configuration files
5. 5. Making Rules
6. 6. Verifying rules
7. 7. Creating Profiles
8. 8. Sysidcfg file
9. 9. Add a host entry
10. 10. Adding a Client
11. 11. Starting The client Installatio

92.What are the main differences between solaris 10 and 9

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The main difference in solaris 9 & solaris 10 is “SMF(Solaris Management Facility)”. In solaris 9, if any service goes down then we should restart all services this is the disadvantage. But in solaris 10,if any service goes down then that particular service we can select and enable it instead of restarting all services.

93.What is OBP and how do you access it?

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Open boot Prom this is 0 run level in solaris

stop+A or in command mode init 0

OBP-OpenBootProm is a firmware which is placed on the sun machine’s prom chip.

it is a os independent user interface to deal with the sun machine’s hardware components.

to access it press stop+A (combination) from keybord.

stop+a command is to boot an interactive boot from the ok prompt

94.What is LOM and how do you access it?

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Lights out management is the abbrevation and some of the Sun severs a use this fecility to emotly operate the Sun sever by conneting a rollover cable from LOM port to a laptop.

There is no need to turn on the server , but if the server is just powered , you can connect the laptop to the LOM port and operate the conected Server. you have to inert the ip address of the LOM port in the IE and by this way you can acess the Server to operate it.