Chapter 6

Question 1

What command is used to examine filesystem acls?

Answer 1

getfacl

Question 2

Which of the following command lines would allow the user elvis to read and write the file /dev/dsp?

Answer 2

None of the above

Question 3

The governors are working on a proposed change to the wrestling laws. Use the output of the following commands to answer the following questions.

[root@station ~]# groups ventura pataki hogan
ventura : ventura wrestle governor
pataki : pataki governor
hogan : hogan wrestle
[root@station ~]# getfacl proposed_wrestling_law
# file: proposed_wrestling_law
# owner: root
# group: governor
user::rw-
group::rw-
group:wrestle:r--
mask::rw-
other::---

Answer 3

-

Question 4

What access does the user pataki have to the file proposed_wrestling_law?

Answer 4

write only

Question 5

What access does the user hogan have to the file proposed_wrestling_law?

Answer 5

read only

Question 6

The user ventura, being both a governor and a wrestler, has chosen to recuse himself. Which of the following commands would not allow ventura to read or modify the file, while the same access is preserved for all other members of the groups governer and wrestle?

Answer 6

setfacl -b ventura proposed_wrestling_law

Question 7

An administrator is configuring access to a /var/contrib directory. Use the output of the following commands to answer the following questions. Assume that “contained files” are files that were created in the directory, with permissions otherwise unmodified, for which the specified person is not the user owner.

[root@station var]# groups elvis einstein
elvis : elvis music wrestle physics emperors
einstein : einstein physics
[root@station var]# ll -d contrib/
drwxrws---+ 2 root music 4096 Oct  1 06:48 contrib/
[root@station var]# getfacl  contrib/
# file: contrib
# owner: root
# group: music
user::rwx
group::rwx
other::--x
default:user::rw-
default:user:elvis:rw-
default:group::r--
default:group:wrestle:r--
default:mask::rw-
default:other::---

Answer 7

-

Question 8

Which of the following may members of the group music (other than elvis) do?

Answer 8

Create files in the /var/contrib directory.
View contained files in the /var/contrib directory.
Remove contained files in the /var/contrib directory.
Obtain a listing of files in the /var/contrib directory.

Question 9

Which of the following may members of the group wrestle (other than elvis) do?

Answer 9

View contained files in the /var/contrib directory.

Question 10

Which of the following may the user elvis do?

Answer 10

EVERYTHINGGGGG

Question 11

Which of the following may the unrelated user einstein do?

Answer 11

None of the above

Question 12

Your friend is trying to create custom acls on a newly created directory in the tmpfs filesystem mounted to /dev/shm.

[root@station ~]# mount
/dev/sda2 on / type ext3 (rw)
proc on /proc type proc (rw)
sysfs on /sys type sysfs (rw)
tmpfs on /dev/shm type tmpfs (rw)
...
[root@station ~] mkdir /dev/shm/contrib
[root@station ~]# setfacl -m u:elvis:rw /dev/shm/contrib
setfacl: /dev/shm/contrib: Operation not supported

Answer 12

-

Question 13

What advice would you give him?

Answer 13

The underlying filesystem must support filesystem acls, and the tmpfs filesystem does not.