Basic networking for a dummy

[1etherer]

I misread the question LMAO...

C is correct! I cant believe how baffling they make it though..

PCs left on over night can connect to the internet.
PCs rebooted in the morning cannot connect to the internet.

DHCP is on its own server, lets say 192.168.1.3
So the PCs left on over night still have 192.168.1.3 as the DHCP server
PCs rebooted in the morning are getting 192.168.1.1 as the DHCP server (which is redirecting to the router, the router has the DHCP disabled)

So the DHCP server has been replaced and not configured correctly.

So C is correct!! LMAO, you really have to read the question a lot!

Does that make sense now Technician?

 

[The Technician]

Nope, lol.

I think I get that DHCP is disabled on the router (it would have been configured that way to begin with if they were using a dedicated server for DHCP, right?).

...PCs rebooted in the morning are getting 192.168.1.1 ...

Why? And from where?

But first, let me see if I understand this correctly...

The old DHCP server was swapped out for a new one. PCs that haven't been rebooted, and haven't lost the old IP info, are still looking for DHCP at the same address. The fact that they can reach the internet leads me to believe that DHCP is properly configured - otherwise, how are these machines getting to the internet? Where are they getting their IPs?

In the case of the PCs that had been rebooted, and thus had released their IP's and would be requesting a new IP, wouldn't they be given an APIPA because they can't connect to DHCP??

From a diagnostics standpoint, the fact that some PCs can reach the internet, and others cannot, leads me to believe that the problem resides in the PCs that cannot connect, and not the DHCP server; if the server were misconfigured, no PCs would be able to connect to the internet. How is it that some can and some can't? Is DHCP giving valid IPs to those that didn't reboot, and invalid one's to those who did?

And now, I am bringing it to my own attention that I don't know how PCs find DHCP server - where do they get the DHCP server's IP? How do they know how to find it?

This is dizzying.

 

[1etherer]

Nope, lol.

I think I get that DHCP is disabled on the router (it would have been configured that way to begin with if they were using a dedicated server for DHCP, right?).



Why? And from where?

But first, let me see if I understand this correctly...

The old DHCP server was swapped out for a new one. PCs that haven't been rebooted, and haven't lost the old IP info, are still looking for DHCP at the same address. The fact that they can reach the internet leads me to believe that DHCP is properly configured - otherwise, how are these machines getting to the internet? Where are they getting their IPs?

In the case of the PCs that had been rebooted, and thus had released their IP's and would be requesting a new IP, wouldn't they be given an APIPA because they can't connect to DHCP??

From a diagnostics standpoint, the fact that some PCs can reach the internet, and others cannot, leads me to believe that the problem resides in the PCs that cannot connect, and not the DHCP server; if the server were misconfigured, no PCs would be able to connect to the internet. How is it that some can and some can't? Is DHCP giving valid IPs to those that didn't reboot, and invalid one's to those who did?

And now, I am bringing it to my own attention that I don't know how PCs find DHCP server - where do they get the DHCP server's IP? How do they know how to find it?

This is dizzying.

Ok Ok, I'm understanding this question completely now 100%!

The PCs that aren't rebooted have the right DNS 192.168.1.1
The PCs rebooted have been given the wrong DNS 192.168.1.2 (by the DHCP)

So the DHCP has been configured to give out 192.168.1.2, when it should give out 192.168.1.1

DHCP gives out internal IPs, and tells PCs the DNS IP.

So the issue is the DHCP server is misconfigured by giving the wrong DNS!

 

[The Technician]

But how do I know that 192.168.1.1 is the correct DNS?

Is DNS always supposed to be the same as the DHCP? As the Gateway?

When I see that DNS is a different IP than DHCP, do I know that it's the wrong DNS?

See what I mean?

 

[1etherer]

But how do I know that 192.168.1.1 is the correct DNS?

Is DNS always supposed to be the same as the DHCP? As the Gateway?

When I see that DNS is a different IP than DHCP, do I know that it's the wrong DNS?

See what I mean?

DNS, DHCP, Default gateway can all be on different IPs (different hardware) or on the same IP (same hardware, router).

For example, in a company,
The router will be the default gateway - 192.168.0.1 (connected to the ISP)
The Domain controller will be the DNS - 192.166.0.5
An additional standalone server will be the DHCP - 192.168.0.6

Note* As you have the DC and server running DNS and DHCP, you can turn them off in the router.

In a home,
You will have a router which acts as default gateway, DNS, DHCP - 192.168.0.1


---
So say your at home and you do IPCONFIG and it says the DNS is 192.168.0.23
and you know your router is 192.168.0.1, then you know there is a problem as the PC has the wrong IP for DNS.

Say your at work and you do IPCONFIG and it says the DNS is 192.168.23.1 and you know you have "2" DNS servers which are 192.168.0.5 and 192.168.0.6 then you know there is an issue as the PC is not pointing to either DNS servers AND is on the wrong subnet.

You will know if the IP is wrong as you set the DNS service up, so you know what the DNS IP should be.

I hope that clears things up?

 

[The Technician]

DNS, DHCP, Default gateway can all be on different IPs (different hardware) or on the same IP (same hardware, router).

You will know if the IP is wrong as you set the DNS service up, so you know what the DNS IP should be.

But in this case, we haven't set up the DNS service ourselves. And the question hasn't supplied us with IPCONFIG info for a PC with connectivity to show us what the correct DNS IP is. So how do you know what the correct DNS IP is? Or, more pertinent to this test question, how do I know the DNS shown isn't the right one?

How do you know it's the same IP as the DHCP server? That's what I don't get.

 

[1etherer]

But in this case, we haven't set up the DNS service ourselves. And the question hasn't supplied us with IPCONFIG info for a PC with connectivity to show us what the correct DNS IP is. So how do you know what the correct DNS IP is? Or, more pertinent to this test question, how do I know the DNS shown isn't the right one?

How do you know it's the same IP as the DHCP server? That's what I don't get.

The log in the question is an ipconfig, and if you cant get internet and have an IP then its most likely a DNS issue.. DNS translates FQDN to an IP.. so if you have the wrong IP then you dont have a DNS.. And you cant get to the internet.

The only IP that will cause an issue in this question is the DNS, if it is incorrect, and the DHCP supplies the DNS so the DHCP server must be mis-configured.

 

[mikesgroovin]

You all are hilarious.

 

[S0ULphIRE]

You all are hilarious.

saw your name pop up in the thread and thought awwww **** we're all about to get schooled

 

[mikesgroovin]

saw your name pop up in the thread and thought awwww **** we're all about to get schooled

I love you too SoulPhire! Gonna sit this one out. But I still like to watch