Your server has a ZFS storage pool that is configured as follows:
The following partition scheme is used for every disk drive in pool1:
Which two are true regarding the ZFS storage pool?
A.
The data on c3t3d0 is duplicated on c3t4do.
B.
The data is striped across disks c3t3d0 and c3t4do and mirrored across vdevs mirror-0 and
mirror-1.
C.
The storage pool is 146 GB total size (rounded to the nearest GB).
D.
The storage pool is 584 G8 total size (rounded to the nearest GB).
E.
The storage pool is 292 GB total size (rounded to the nearest GB).
A and E
In mirroring concept if you have two harddisk 10GB, 10GB. and you create mirroring in both harddisk, you have get 10GB for use. not 20GB… so in this question you goet 146GB not 292GB…..
Hi Mir,
We not looking for a total size of each mirror but the total size of the whole pool1.
Here is a real life example for you (I’ll use 1GB dummie disks but it still the same concept):
1. Made 4x1GB dummie disks
root:/var/tmp/vdisks# ls -al
total 7477334
drwxr-xr-x 2 root root 6 Aug 12 09:59 .
drwxrwxrwt 8 root sys 14 Aug 12 09:57 ..
-rw——T 1 root root 1073741824 Aug 12 09:58 c3t3d0
-rw——T 1 root root 1073741824 Aug 12 09:58 c3t4d0
-rw——T 1 root root 1073741824 Aug 12 09:59 c3t5d0
-rw——T 1 root root 1073741824 Aug 12 09:59 c3t6d0
2. Created a pool1 and mirrored according to the above scenario
zpool create pool1 mirror /var/tmp/vdisks/c3t3d0 /var/tmp/vdisks/c3t4d0 mirror /var/tmp/vdisks/c3t5d0 /var/tmp/vdisks/c3t6d0
root:/var/tmp/vdisks# zpool status pool1
pool: pool1
state: ONLINE
scan: none requested
config:
NAME STATE READ WRITE CKSUM
pool1 ONLINE 0 0 0
mirror-0 ONLINE 0 0 0
/var/tmp/vdisks/c3t3d0 ONLINE 0 0 0
/var/tmp/vdisks/c3t4d0 ONLINE 0 0 0
mirror-1 ONLINE 0 0 0
/var/tmp/vdisks/c3t5d0 ONLINE 0 0 0
/var/tmp/vdisks/c3t6d0 ONLINE 0 0 0
errors: No known data errors
3. Now lets check the total size of pool1 and according to you incomparison with your above statement, this should be 1GB and not 2GB
root:/var/tmp/vdisks# zpool list
NAME SIZE ALLOC FREE CAP HEALTH ALTROOT
pool1 1.98G 526K 1.98G 0% ONLINE –
There you go, storage pool total size is 2GB. Answer A & E 🙂
Hi Mir,
Your are right but then there are two mirrors in the pool, of course each mirror will only show 146GB, but if you multiply that by 2 you get 292GB for the pool. mirror 0 146GB, mirror 1 146GB and pool 1 292GB
A,E
A&E is correct.
There is mirroring and stripping across.
Phumlani scenario explained it more.
regards