Sysadmin Questionaire

Sysadmin Questionaire

If you have ideas or notes or improvements, please create an account and i’ll open this up for editing. I want this list to be a great reference.

Scoring: 1 point for each correct answer, zero for “I don’t know” or an incorrect answer clearly identified as a guess, and -1 for obvious guessing or bs-ing. Basic Level Questions

  1. What do you consider your level of experience to be on a scale from 1 to 10 with 10 being Dennis Ritchie and 1 being a luser?
  2. Length of experience as a Unix user, as a System Admin.
  3. Describe what a day of system administration might be for you?
  4. How do you currently interface with customers?
  5. What is one of the more recent problems that you solved as a sysadmin.

Basic Sysadmin

  1. What Operating Systems are you familiar with
    1. HPUX
    2. Solaris
    3. SunOS
    4. OSX
    5. BSD ( which variant )
    6. IRIX 6.x
    7. AIX
    8. OSF/1 / Ultrix
    9. Linux ( which variant )
    10. TOPIX ( fat chance )
    11. SCO / XENIX
    12. UNICOS
  2. Identify 5 options to the `ls’ command and what they produce.
  3. How many fields are there in a standard BSD 4.3 /etc/passwd file, without shadow password or other extentions?
  4. What is the default login shell if that field in /etc/passwd is left blank?
  5. What are the limitations on a user login name in /etc/passwd?
  6. How many characters are significant in a standard passowrd?
  7. What is the difference between sections 1 and 8 in the UNIX manual set?
  8. What is the difference between sections 4 and 5 in the UNIX manual set?
  9. What is the difference between sections 2 and 3 of the UNIX manual set?
  10. What does ‘init’ do and where does it live?
  11. Where would you find the numeric value of the SIGPIPE signal?
  12. What is the primary difference between SIGKILL and SIGTERM manual set?
  13. How do you unpack neattoy.tar.gz.shar.uu?
  14. What three commands are used to modify file ownership and permissions?
  15. What shell does cron(8) execute commands in?
  16. Name the 5 fields to cron.

User Environment

  1. When is a user’s .cshrc file executed and when is his/her .login executed relative to .cshrc?
  2. What is an advisable way to set your PATH environment variable to protect yourself from unintentionally invoking trojan horses?
  3. What files, ownerships and permissions must be set for rsh to work?
  4. What umask value would prevent anyone but you from writing or executing your files but still allows reads?
  5. What is the difference between the real and effective UID of a process (UID vs. EUID).
  6. What command can a user use to see what his uid and groups are?
  7. What command is used to set the TERMCAP environment variable?
  8. What does the ‘resize’ command do and why won’t it work unless Xwindows is installed?

Installations

  1. How much room would you allocate for the primary filesystems ( /, /usr, /tmp, /var, /home, etc.. )?
  2. Why do the same binaries exist in /bin and /usr/bin ( sh, ls )? What is the difference between them?
  3. Name some packages that you generally install on every system.. why?
  4. How much swap space should you allocate for a system?

X Windows

  1. What is the difference between .xinitrc and .xsession?
  2. Where is the configuration information for xdm?
  3. How would you add a new font to Xwindows?
  4. What does xhost do? Why is xhost bad?
  5. What does xauth do? Why is it good? What is a cookie?
  6. In what ways can a user customize his X environment for xterm?
  7. Name some window managers you are familiar with ( fvwm[1.24|2|95], mwm, olvwm, tvtwm, ctm, enlightenment, kwm, etc.. )

The Filesystem

  1. What is the easiest way to tell which disk partition a particular file resides on?
  2. Describe an Inode and what it does.
  3. What is the difference between a hard link and a soft link?
  4. How do you make a link to a directory?
  5. How does the fsck(8) command determine in which order to check the filesystems at boot time?
  6. What is the “u” option to the dump command and why would you use it?
  7. What is the difference between /dev/sd0a and /dev/rsd0a?
  8. Where are system libraries kept?
  9. What does chroot do?
  10. If you are trying to unmount a filesystem, and the system says it is busy, how would you find out why?
  11. Where is the FAT and what do you do if it is corrupted?
  12. If you have hundreds of thousands of files in a directory, and you want to delete all but the ones that start with the letter “a”, how would you do it? ( contributed by Jason Fesler )

Networking

  1. What is the difference between a gateway and a router?
  2. What does the `archie’ tool do?
  3. What does a file named ‘blah’ linked to the rlogin program do?
  4. What is the class designation of an IP address (A, B, or C) used to determine?
  5. What class of IP address is 128.138.243.8?
  6. How many addresses does a 172.16.52/8 network have that are usable?
  7. What does the 127.0.0.1 address do? The 224.0.0.0 network?
  8. How many terminators does an Ethernet network have?
  9. Which system or systems on a network answers an ARP request packet?
  10. To use a serial port for both dial-in and dial-out, how must the system and modem be configured?
  11. Why should ‘routed’ always be run with the -q option or not run at all?
  12. What advantages does gated have over routed?
  13. How does one view the routing tables?

Printing

  1. What does the -m option to lpr produce?
  2. What is the command which controls or manages the BSD line printer daemon?
  3. What is the separator between messages in a UCB mbox mail file?
  4. What are some differences between BSD printing and SYSV printing?
  5. What must a text file begin with to be recognized as PostScript code?
  6. What is the difference between PostScript and Encapsulated PostScript?
  7. What is the `lf’ parameter used to designate in an lpd printer configuration (printcap) entry and why should you always define it?
  8. What do ‘if’ and ‘of’ do .. what is the difference between them?
  9. Name some common commands to lpc, to lpadmin.
  10. What is the configuration file for BSD printing? the directory structure for SYSV?
  11. What is CUPS?

Email

  1. How do you forge mail “From santa.claus@northpole.org”?
  2. What port(s) does email use?
  3. If a user has a mail loop, what things should be checked at both systems involved to determine the source of the problem?
  4. Sendmail
    1. What option to sendmail invokes rule parsing test mode?
    2. What option to sendmail runs it as a daemon?
    3. How do you create sendmail configurations on the fly?
  5. Postfix
    1. What file is used to configure postfix?
    2. Why is it better/worse than sendmail

Disk Hardware

  1. SCSI
    1. How many SCSI devices can be connected to a workstation with a single SCSI controller interface?
    2. What is the SCSI id number of a workstation SCSI controller interface?
    3. If a SCSI hard disk was formatted on a Sun and no data has yet been written to it, what needs to be done to use it on a non-Sun UNIX system?
    4. If you’ve been using a SCSI hard disk on a Sun, what do you need to do in order to move that disk to a non-Sun UNIX system and preserve the data.
  2. ATA
    1. Where is the controller for an ATA disk?
    2. How many disks can be on an ATA cable?
  3. SATA
    1. Where is the controller for an SATA disk?
    2. How many disks can be on an SATA Chain?
  4. USB/Firewire
    1. What are the speeds of FW400, FW800, USB1.x, USB2.x
    2. How many disks can be on a USB chain?
  5. ISCSI
    1. How does iSCSI work?
  6. What information is stored in a disk label?
  7. How does one format a disk ( newfs, mkfs, format )?

NFS

  1. Via NFS, by default the root access is enabled or disabled?
  2. On an NFS mounted filesystem, is a soft link is evaluated (followed) in the server hierarchy or client hierarchy?
  3. When you change /etc/exports, what must be done for mountd to recognize and incorporate the change?
  4. With what command can you see what another host is
  5. What is an automounter? What automounters are you familiar with? What is the difference between automounter and amd?
  6. What happens to the client when an NFS server goes down?
  7. What is a Stale NFS Handle? What can you do to get rid of it?

NIS

  1. Describe the client server relationship between a Yp server, a yp slave and a yp client.
  2. Describe how data is propegated to slaves from servers.. include a client.
  3. What happens to the clients on a subnet if the server crashes.
  4. How do you rebind ypbind?
  5. How do you view a ypfile on a client? the raw file on a server?
  6. How does a client locate a ypserver?
  7. How does a slave server know that maps on the master have changed?
  8. Why is it faster for ypxferd to transfer files? Where should it be run?
  9. Where does yppasswdd run… how does it work?

Backups

  1. What do you use to perform backups?
  2. What are the advantages of dump, tar, cpio ?
  3. What are some backup softwares you are aware of?
    1. omniback
    2. amanda
    3. bacula
    4. Time Machine
  4. What is the difference between a level 0 and a level 1 backup?
  5. Why not do backups when users are active?

Kernel Management

  1. Where are the files which are used to re-build a kernel? ( BSD / SYSV / OS Specific )
  2. What is the procedure for building a new kernel from a kernel configuration file?
  3. Name some configuration parameters that you generally change in a kernel ( MAXFILES, number of users )

DNS

  1. What file must be configured on all DNS clients and what are the minimum two lines it must contain to function?
  2. What ways may an IP can be resolved and how do you set the order? ( WINS, DNS, local files, NIS, LDAP ()
  3. What is the configuration file for named?
  4. What does the trailing dot signify in a db file?
  5. What must one do to have named know there’s an update in a config file?

Scripting

  1. Perl
  2. Name the three basic data types in perl?
  3. How would you use a case statement for perl?
  4. What does TIMTOWTDI mean? What is the camel and the llama?
  5. What is the difference between a package and a library?
  6. Name some perl modules you have used?
  7. Ruby
  8. What is rails?
  9. Give me an example of chained method calls?
  10. General
  11. How does the system determine which shell to invoke to execute a shell script?
  12. What shell is used for default system bootup scripts?
  13. What are some differences between sh and csh? csh and tcsh? sh and bash? ksh and zsh?

Editors

  1. What’s your favorite editor?
  2. What are the keystrokes to change ’emacs’ to ‘vi’ in a file using vi?
  3. What can you use to edit a binary file?

Porting software

  1. Have you ever built any open source softare from the ground up?
  2. Have you ever ported software to an unsupported platform?
  3. Do you know how to modify a Makefile?

Security

  1. Where do you get your security information from?
  2. Name the last two security holes that you have plugged.
  3. What does a firewall do?
  4. Name some security software that you have used on your machines. ( Crack, cops, tcpd, fwtk )
  5. What does unix use by default to encode passwords? What is it’s strengths? it’s weaknesses?

Syslogging

  1. how does syslogging work?
  2. what are some of the facilities and priorities in syslog?
  3. what command can you use to make a syslog entry?

Specific Operating Systems

HP-UX

User Administration

  1. How can you force a user to change his/her password when she next attempts to login?
  2. What keys can be used for backspace and delete ( as defined by stty ) at the login prompt?

Disk Administration

  1. What is a volume group? A physical volume? A logical volume? A physical volume group?
  2. What is the advantage of vxfs over hfs? What extensions to that do Online JFS give you?
  3. How can you see what disks are assigned to what devices?

System Administration

  1. Where are the initilization scripts kept? Where are the configuraion files kept?
  2. How would you edit the password file? Why not use vi?
  3. What happens if you edit the password file when the root filesystem is full and you try to write the file? Why is that bad?
  4. How do you install a patch from HP? What is a software depot?

Linux

User Administration

  1. How does one add a user
  2. What file controls user password length and expiration?

System Administration

  1. Where is the system configuration?
  2. How does one enable a service?
  3. How do you install packages?
  4. What is a volume group? A physical volume? A logical volume? A physical volume group?

Network Administration

  1. How does one see the configured interfaces?
  2. How do you see if an interface has more than 1 IP address assigned?
  3. How does one see the routes defined for this system?
  4. Where is the hostname defined?

MacOS

User Administration

  1. How does one add a user to a Mac System?
  2. What’s the difference/separation between NetInfo and local files?
  3. Where are system startup scripts kept?
  4. Where are user preferences kept?