You work as a network administrator at ABC.com. The ABC.com network consists of a single
domain named ABC.com. All servers on the ABC.com network have Windows Server 2012 R2
installed.
The network as a server named ABC_SR05 that provides DHCP services. You need to create a
new IPv4 subnet on the network. The subnet must support a maximum of 5,000 hosts and must
have a few unused addresses as possible.
How would you configure DHCP to support this subnet?
A.
You should use a subnet mask of 255.255.255.0.
B.
You should use a subnet mask of 255.255.248.0
C.
You should use a subnet mask of 255.255.240.0.
D.
You should use a subnet mask of 255.255.224.0
E.
You should use a subnet mask of 255.255.128.0
F.
You should use a subnet mask of 255.255.0.0
Explanation:
It’s wrong ; Correct answer is D :
/19 13 255.255.224.0 213-2 = 8190 hosts
255.255.224.0 mask permits only 4096 hosts.
Can you post your calculation pls.
The last octet totals 256 (ignore the network and broadcast addresses unless the number asked is close). For each bit used in the third octet double the number of hosts. 512, 1024, 2048, 4096, 8196. That’s 5 bits used in the third octet, leaving 3 bits left. 128 + 64 + 32 = 224.
Oops again. Of course, the last total should be 8192. Again, forget the network and broadcast unless it’s close.
The subnet must support a maximum of 5,000 hosts.
/19 13 255.255.224.0 213-2 = 8190 hosts are too much. So 255.255.224.0 with 4094 hosts is right!
Wrong. 4096 is not at lease 5,000 hosts (+2 network & broadcast).
The correct answer is, in fact, D
Im wrong again….
Max=5,000
still seems like tricky wording tho
aale dieter, read carefully “The subnet must support a maximum of 5,000 hosts and must
have A FEW UNUSED ADDRESS AS POSSIBLE” 5000-4094=906. Lack of 906 addresses… There had to 4000 hosts instead of 5000 ones I think!
The answer is D. With 8190 possible hosts this is more than 5,000 host required. Answer C provide only 4000 hosts and cannot satisfy the 5000 host requirement.
Robert i should think so too as its stated maximum of 5000 hosts.
Yup, ok. Max 5,000.
Seems like a silly requirement….but maybe not
Wording isn’t really that tricky. It must support max of 5000 hosts. 255.255.240.0 does not support that many, only 4096, so it cannot be the answer. 255.255.224.0 supports 8192 hosts, so it is the clear answer, when you consider that the answer has to have as few unused as possible which eliminates E and F as answers. Answer is D.
255.255.248.0 = 2046 hosts
255.255.240.0 = 4094 hosts
255.255.224.0 = 8190 hosts
255.255.128.0 = 32766 hosts
255.255.0.0 = 65534 hosts
Depending how you read it answer it! I choose D but may also go with C…. 🙂
C is correct. Max at 5000, not to go over that amount.
I believe the correct requirement would be ‘minimum 5000 hosts’, making the D answer correct.
The ‘maximum 5000 hosts’ version is too ambiguous
Answer C is correct considering max 5000 host. we need to take this into account.
The questions says
“The subnet must support a maximum of 5,000 hosts and must
have a few unused addresses as possible.”
if the answer was indeed c, what would happen when the site needed all 5000 ip’s?
the trick in in the “Must support a maximum of 5,000” C does not support that maximum
the correct answer is D as it can Support over 5,000, second part of the question “and must
have a few unused addresses as possible.” is there to make E and F wrong as those 2 provide many more unused ip addresses than option d