Linux Essentials 2.0 Chapter 16 Exam Answers

L ns Liiin nu ux x Esss sse sse en n ntttiiia a alllss 2..0 0C Ch h ha a ap p pttte e err 1 16 6E Ex x xa a am m An nsw ssw we errss e w 1-49 -49 a res sser 1. UI UIDs Dss 1-4 499 9a ar are re u usu ssu ual ua all lly y re ese erv ved ed d ffo for orr w what att ki kind in nd do off use e ers rs? rss? 11 D ser e rrve wh Remote log-in accounts Are not used for user accounts, but for group accounts System accounts, such as server processes Log-in (human) users • • • • 22 an 2. If If a u use ser ser is d de e elle ettte ed, ed tth the he e ffi file les le ess a and nd d dir ire rec ector torie ie ies ess tth ha att tthe he u use ser err o ow own wne wn ned ed… d… di us …will have no user owner. …will have no UID owner. …will show a UID as the owner, but not user name. …are deleted as well. • • • • 33 off tth opt w 3. Wh Whic ich ich o he e ffol fo ollowi w wiin ng g opti ption onss fo for o orr tthe he useradd co comma ma man an and nd da all lllo llllo o ow wss ro p ob wiit roo oot o ott to to sspe sp pec ecif ciiify fyy tth the eU UI UID ID tto be e as asso ssoc ocia oci ciat ate tte e ed dw ith tth h tth the he he a acc ccou oun unt un nt? t? ac -g -G -u -M • • • • 44 off tth opt w 4. Wh Whic ich ich o he e ffol fo ollowi w wiin ng g opti ption onss fo for o orr tthe he useradd co comma ma man an and nd da all lllo llllo o ow wss p e tthe e m rro o oo o ott tto o ssp pec eci ecify fy ssu up uppl pp pllem e em men me ent nta tar ary ry gr gro roup u ups ps ps th he us user se err w wil eam me emb em mbe ber er wiillll be off?? o -G -u -g -U • • • • 5. O On ysttem em th ttha us co n a ssys hat at do doe oe oes es n not ott u use UP PG G G,, tth the he useradd com omm mma man and nd dw wilillll no wi als e lso o ccr crea eat ea ate te eau ussse err gr group rou up. p.. F Fo For o orr exam e amp mpl ple le le,, u user er bob, gr gro ro rou oup ou bob. Tr Tru ru rue ue e orr Fa Fal als lse sse e?? True False • • 66 e fo ffol cco h 6. Wh Whic ich ch ho off tth he ollllowi win ing ing com omma man and ndss wi will a add dd d tth the he group up extra to o the he tth us r ‘s se g u i n a d i t t ‘s cu s o use sse er bob‘s sec eco condar ary ry y gro roup ups pss ad d dd diiti ittio ion on n to bob‘s cur curr rren rrent ntt se eco cond c nda d da ary arrry n ar gr gro roup ups ps? s? usermod -G extra bob usermod -ag bob extra usermod -aG extra bob usermod -a extra bob • • • • 77 op ffor us 7. Wh Whi hiiccch h opt pti tio io ion o on n fo orr tth the he usermod co comma mand n nd d cca an eu use sed se ed d tto o ssp speci ci cif if ify ffy ya nb be us e D ((ei e e prrriima im orr ssec e a usse er’ errr’ss gr group up p IID (e eit eiith ther he err p mar ar ary se eco cco ond on n nd dar da ary ry ry) y)? )? yo (c hoos ttwo (cho ch hoo ose se tw w wo o)) -s -g -S -G • • • • 88 mand n cca yb 8. For orr nonn n-ro roo oot ott u us use ser er ers rs, tthe th he passwd co com o om mma an can an n on onl n nlly eu use sed ed d to be to ch pa off tth e ru rrun tth h e cco d cha han an ang nge e tth the he ep pass ssw swo wor ord rd do the he u se er unn nn niiing n ng g the com om omm mma m ma man a an nd. d. usser Tr Tru ru rue ue e orr Fa Fal als lse sse e?? • True • False 9. The groupmod command can be used to change a group name. True or False? • • True False 10. The groupmod command can be used to change a group GID. True or False? • • True False 11. The groupmod command can be used to add users to a group. True or False? • • True False 12. Which of the following commands can be used tto o modify a group? • • • • groupmod groupadd modgroup addgroup 13. Which command can be u used sed to determine a user’s most recent log in? • • • • history last login shell 14. Which of the following files contains encrypted user password inf information? ormation? • • • • 15. /etc/usr /etc/group /etc/passwd /etc/shadow Which of the following files contains user IIDs? Ds? • • • • /etc/group /etc/passwd /etc/usr /etc/shadow 16. Which of the following files does the groupadd command u use se to determine the new GID when a GID isn’t specified? • • • • /etc/usr /etc/shadow /etc/passwd /etc/group 17. Which of the following commands, run as root, will prevent the user bob from logging in? • • • • 18. usermod -L bob usermod -l bob usermod -D bob usermod -d bob What dir directory ectory contains a user’s home directory? /user / • /home • /rootfs • • 19. GIDs under 500 (or 1000) ar are e usually reserved for what kind of groups? System use Are not used for groups, but for user accounts Administrators User private groups (UPG) • • • • 20. If a user is deleted, the fi files les and directories that the user owned… …are deleted as well. …will have no user owner. …may be important for others in the organization …will have no UID owner. • • • • 21. Which of the following options for the useradd command allows you to use a different primary group then the default? -g -G -U -u • • • • 22. On a system that uses UPG, the UID must not be the same as the GID.. True or False? True False • • 23. The usermod ccommand ommand can b be e used to unlock a users account with the following option. -s -u -f -U • • • • 24. Which of the following options for the useradd command allows you to use a differ different ent login shell than the default? -g -s -u -U • • • • 25. Which of the following commands will add the group extra to the user jane’s secondary groups in addition to jane‘s curr current ent secondary groups? usermod -a extra jane usermod -ag jane extra usermod -aG extra jane usermod -G extra jane • • • • 26. Which option for the usermod command can be used to specify a user’s primary group ID? -g -S -G -s • • • • 27. For root users, the passwd command can only be used to change the password of the user ru running nning the command. True or False? • • 28. • True False The userdel -r command will… …will prompt before deleting each file owned by a user. • • • …delete the user account, but leave the user’s files by default. …automatically delete a user and the user’s home directory and mail spool and their contents. …automatically delete a user and all the files owned by that user. 29. The groupmod command can be used to change a group name. True or False? • • True False 30. The groupmod command cannot be used to change a group GID. True or False? • • True Fasle 31. The groupdel command can be used to delete primar primary y groups. True or False? • • True Fasle 32. Which of the following commands can be used tto o modify a user? • • • • adduser moduser useradd usermod 33. Which command can be used to determine a user’s most recent log in? • • • • history shell login last 34. The /etc/passwd fi file le contains enc encrypted rypted u user ser password information. Tr True ue or False? True or False? • • 35. False True Which of the following files contains group IDs? • • • • /etc/passwd /etc/usr /etc/shadow /etc/group 36. Which command allows you to view or change some of the default values used by the useradd command? • • • • useradd -D useradd -r modvalue useradd -f 37. Which of the following commands, run as root, will prevent the user jane from logging in? • usermod -d jane • • • usermod -D jane usermod -L jane usermod -l jane