Strange sample question for 70-291

I came across the following sample exam question that seems to be a
"trick" question and was hoping someone can provide help -



You are the network administrator for [moderated].net. The network
consists of two subnets separated by routers. The network is
configured as shown in the exhibit ([X] represents a router):


DHCP---subnetA-----Interface:10.10.10.65[X]Interface:10.10.10.93

|

subnetB

Subnet A is connected to a router that has the IP address 10.10.10.65.
It
contains five client computers. All the client computers receive their
IP configuration from a local DHCP server. The scope configuration of
the DHCP server is shown in the following table.

IP address range 10.10.10.66 to 10.10.10.70
Subnet mask 255.255.255.192
Default gateway 10.10.10.65

Subnet B is connected to a router that has the IP address 10.10.10.93.
It
does not contain any computers yet. You install a new Windows Server
2003 computer named SERVER1 and connect it to the subnet B
network. The TCP/IP configuration of the new computer is shown in the
following table.

IP address 10.10.10.94
Subnet mask 255.255.255.240
Default gateway 10.10.10.93
Users in subnet A report that they cannot connect to SERVER1. You need
to enable the client computers in subnet A to connect to SERVER1.
What should you do?

A. Create a new scope on the DHCP server to assign the client
computers in subnet A a subnet mask of 255.255.255.224.
B. Change the scope options of the DHCP server to assign the client
computers in subnet A a default gateway of 10.10.10.93.
C. Change the subnet mask of SERVER1 to 255.255.255.192.
D. Change the default gateway of SERVER1 to 10.10.10.65.



The answer is C.

I understand why the answer is C, as the IP address of SERVER1 would
be invalid for its subnet mask since 10.10.10.94 would be the
broadcast address for the network under a /28. Changing to a /26
allows 10.10.10.94 to be used.

However at the same time, when clients in subnetA attempt to contact
SERVER1, they are in a /26, so with address .66 - .70, .94 would
actually be local to them and therefore the packets would not be sent
to the default gateway and would never reach the router in the first
place. So with answer C, I don't believe this problem would be fixed.
Am I missing something here?

kcsteele

On Jan 31, 7:57 am, "kcsteele" <k.c.ste...@gmail.com> wrote:
> I came across the following sample exam question that seems to be a
> "trick" question and was hoping someone can provide help -
>
> You are the network administrator for [moderated].net. The network
> consists of two subnets separated by routers. The network is
> configured as shown in the exhibit ([X] represents a router):
>
> DHCP---subnetA-----Interface:10.10.10.65[X]Interface:10.10.10.93
>
> |
>
> subnetB
>
> Subnet A is connected to a router that has the IP address 10.10.10.65.
> It
> contains five client computers. All the client computers receive their
> IP configuration from a local DHCP server. The scope configuration of
> the DHCP server is shown in the following table.
>
> IP address range 10.10.10.66 to 10.10.10.70
> Subnet mask 255.255.255.192
> Default gateway 10.10.10.65
>
> Subnet B is connected to a router that has the IP address 10.10.10.93.
> It
> does not contain any computers yet. You install a new Windows Server
> 2003 computer named SERVER1 and connect it to the subnet B
> network. The TCP/IP configuration of the new computer is shown in the
> following table.
>
> IP address 10.10.10.94
> Subnet mask 255.255.255.240
> Default gateway 10.10.10.93
> Users in subnet A report that they cannot connect to SERVER1. You need
> to enable the client computers in subnet A to connect to SERVER1.
> What should you do?
>
> A. Create a new scope on the DHCP server to assign the client
> computers in subnet A a subnet mask of 255.255.255.224.
> B. Change the scope options of the DHCP server to assign the client
> computers in subnet A a default gateway of 10.10.10.93.
> C. Change the subnet mask of SERVER1 to 255.255.255.192.
> D. Change the default gateway of SERVER1 to 10.10.10.65.
>
> The answer is C.
>
> I understand why the answer is C, as the IP address of SERVER1 would
> be invalid for its subnet mask since 10.10.10.94 would be the
> broadcast address for the network under a /28. Changing to a /26
> allows 10.10.10.94 to be used.
>
> However at the same time, when clients in subnetA attempt to contact
> SERVER1, they are in a /26, so with address .66 - .70, .94 would
> actually be local to them and therefore the packets would not be sent
> to the default gateway and would never reach the router in the first
> place. So with answer C, I don't believe this problem would be fixed.
> Am I missing something here?

Edit: Actually, .95 is a broadcast address under a /28, not .94, so
now I don't even know why C is the answer at all...

kcsteele

> >C. Change the subnet mask of SERVER1 to 255.255.255.192.

> >The answer is C.

Yes, it is correct

> > However at the same time, when clients in subnetA attempt to contact
> > SERVER1, they are in a /26, so with address .66 - .70, .94 would

Yes, same subnet(/26), but separated by router, by default router block this
traffic:

bootps 67/udp dhcps #Bootstrap Protocol Server
bootpc 68/udp dhcpc #Bootstrap Protocol Client

> > actually be local to them and therefore the packets would not be sent
> > to the default gateway and would never reach the router in the first
> > place. So with answer C, I don't believe this problem would be fixed.
> > Am I missing something here?

Yes, router

=?Utf-8?B?T1RITUFO?=

On Jan 31, 9:42 am, OTHMAN <OTH...@discussions.microsoft.com> wrote:
> > >C. Change the subnet mask of SERVER1 to 255.255.255.192.
> > >The answer is C.
>
> Yes, it is correct
>
> > > However at the same time, when clients in subnetA attempt to contact
> > > SERVER1, they are in a /26, so with address .66 - .70, .94 would
>
> Yes, same subnet(/26), but separated by router, by default router block this
> traffic:
>
> bootps 67/udp dhcps #Bootstrap Protocol Server
> bootpc 68/udp dhcpc #Bootstrap Protocol Client
>
> > > actually be local to them and therefore the packets would not be sent
> > > to the default gateway and would never reach the router in the first
> > > place. So with answer C, I don't believe this problem would be fixed.
> > > Am I missing something here?
>
> Yes, router

doesn't matter, question states that server1 already has an IP address
so DHCP has nothing to do with it. I already spoke with someone else,
this is simply a botched question. Even with a /26, computers in
subnetA are /28 so when attemping to contact SERVER1 the packets will
not be sent to the default gateway and will never reach the router.

kcsteele