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DHCP

My scenario is this

i have two domains(old and new).as of now iam in process of transferring all roles and data to the new domain. all r fine ok...good

but the problem i face is with dhcp.i exported the conf of dhcp from old server and put it on a win 2003 server in the new domain.i assigned the new gateway & new dhcp and changed the dns domain name on the dhcp in new server.i authorize the new dhcp server and unauthorised the old one...but the clients are not getting ip address from the new dhcp server .....

OK tried a lot of things

This is my situation now friends

The wireless clients are getting IP from the new dhcp server

Ip details for wireless network

10.2.32.1 to 10.2.32.254

subnet mask is 255.255.255.0

Default gateway in the new dhcp is 10.2.32.21

Dns is 10.2.32.20

As for the Lan Clients they are not getting IP from the new DHCP Server

IP details for lan clients:

10.2.34.1 to 10.2.34.254

subnet 255.255.255.0

gateway in the new dhcp is 10.2.32.21

dns is 10.2.32.20

Even when i assign static ip i get a message showing,the default gateway is not on the same segment that is defined by the ip address and the subnet mask.do you want to save this configuration??

After that i get a warning also



Now i figured out something...

The dhcp works with the old DNS(10.2.32.11) address when i assign static ip on clients even if the gateway is 10.2.32.21(tmg),and they are able to access internet

But when i change the DNS to new server(10.2.32.20) the clients are not able to connect.....

this was my previous situation

nw everything figured out

and the situation is

the clients are getting the IP from the new dhcp server.....

Wireless clients have access to internet and is working

The lan clients, it shows local and internet,bu there is an exclamation mark and it says unathenticated and is not able to access the internet
Please help me friends

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riazambalath
Asked:
riazambalath
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1 Solution
 
computerdoctorserviceCommented:
Can you show the results of "ipconfig /all" from one of the client's machines?
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Sikhumbuzo NtsadaCommented:
It seems to e a misconfiguration, check your and see if it the DNS IP corresponds with it, see also if you inserted the DNS IP address on the Router's configuration to be sent by your DHCP scope.
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Sikhumbuzo NtsadaCommented:
"scope"
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chakkoCommented:
Seems like a possible VLAN problem.

The PCs are on a different network than your server (DHCP).  does the old server have multiple network cards?  
Can you try to plug the new server into the same switch port as the old server.  This is to check if that switch port for the old server is configured for the VLANs.

Also, in the old scope on the old server, for the DHCP scope for the PC's what is the default gateway setting there?

Lastly, you might check the local routing table on the old server.   Dos command route /print
then look for any entries related to the 10.2.34.0 network.  you might have some setting there, probably not, but a good idea to check it.
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chakkoCommented:
Just read your post again.  So is the  only problem now that Pc's are not able to access the internet when using the new server as DNS?
On the new server can you access the internet?  What DNS settings are in the TCP/IP of the new server?
You may need to configure a forwarder in the DNS on the new server.  Open DNS manager, click your server then Properties.  There is a forwarder tab.  You should enter an external DNS as a forwarder.
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riazambalathAuthor Commented:
Reply to comment ID:35504422

the dhcp server is 10.2.32.12.....

subnet is 255.255.255.0

gateway is 10.2.32.1(core switch)

dns is 10.2.32.20(DC)

through the dhcp i configure the scope options with router(gateway) of 10.2.32.21(tmg) and dns as 10.2.32.20(dc)

the wireless clients are all using 10.2.32. vlan ....all are working fine....

The lan clients are 10.2.34,10.2.40.10.2.60 etc.......all the lan clients are getting the ip from the DHCP server and it shows local and internet,but the problem is there is an exclamation mark in  a triangular box and it says unauthenticated.....

all lan clients are yet to be joined the new domain....

i doubt my tmg is the cause for this.....

any ideas friends???

The lan clients are on

10.2.




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chakkoCommented:
Sorry, but where is the triangle (unauthenticated) at?  on the PC or on the DHCP console?

with subnet 255.255.255.0 then you have multiple network subnets - different networks.
10.2.32.0 is a different network than 10.2.34.0
On the old server check the TCP/IP settings of the network card.  Is the subnet mask 255.255.0.0?
if the correct subnet mask is 255.255.255.0 then you have to have some routing somewhere so that the subnets can reach each other.  Probably you have some routing table in the switch to interconnect the VLANS.

If you need a network of 10.2.x.x then try changing the subnet mask to 255.255.0.0  then all IPs in 10.2.0.0 to 10.2.254.254 will be in the same network.

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riazambalathAuthor Commented:
the triangle is at the client pc's....(vista machines),even the xp machines doesnt connect to the internet..

The subnet is exactly the same...255.255.255.0

i do have routing at my core switch....

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chakkoCommented:
my first thought is there is some mojo going on in your system :)

My normal thinking is that for the PC's on the 10.2.34.x network they will need a gateway of something like 10.2.34.1, then the switch routing will handle the rest
Can you try to ping 10.2.34.1 and see if you get a response.  Or can you view the switch routing to see what is configured there?
If you get a reply from 10.2.34.1 then try to configure a PC with manual TCP/IP settings such as
IP   10.2.34.44
subnet mask: 255.255.255.0
Gateway:  10.2.34.1
Dns:  your normal dns server setting

Then try to ping an internet address.  Successful?  then try to ping something on the internet by name?  Success?

please report what you get.

If it works then I would think you need multiple scopes for each network segment on the DHCP server.
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riazambalathAuthor Commented:
Reply to ID:35505793...

am out of office now...

will try the same tomorrow and i will report.....


Thank You very much for your time......
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riazambalathAuthor Commented:
Reply to ID:35505793

Tried manual settings also...

still it shows local and internet....but no access
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chakkoCommented:
were you able to find an address to ping at the switch on the 10.2.34.x range?

have you looked at the switch configuration.  Do you see any settings of 10.2.34.x?  what are they for?
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riazambalathAuthor Commented:
Yes i can ping a computer in  10.2.34 and 10.2.130(another vlan).......
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chakkoCommented:
can you ping the TMG  (10.2.32.21)?
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chakkoCommented:
can you ping the TMG  (10.2.32.21)?
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riazambalathAuthor Commented:


i cannot ping the tmg 10.2.32.21 and even the dc 10.2.32.20
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chakkoCommented:
what is the IP of computer you are using / testing with?

can you ping 10.2.32.1?
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riazambalathAuthor Commented:
10.2.130.56


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riazambalathAuthor Commented:
when i tried the troubleshooter in the client machine it says...cannot contact with the primary dns.....
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chakkoCommented:
from the same pc:

please try tracert 10.2.32.21  and post the results

also try tracert 10.2.34.??  some pc in the 10.2.34 and post the result

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riazambalathAuthor Commented:
C:\Users\riaz.ambalath>tracert 10.2.32.21

Tracing route to qitstmg.qitsqatar.com [10
over a maximum of 30 hops:

  1     3 ms     1 ms     1 ms  qitstmg.qi

Trace complete.

C:\Users\riaz.ambalath>tracert 10.2.130.56

Tracing route to simple-pc.qitsqatar.com [
over a maximum of 30 hops:

  1    <1 ms    <1 ms    <1 ms  simple-pc.

Trace complete.

C:\Users\riaz.ambalath>tracert 10.2.34.122
^C
C:\Users\riaz.ambalath>tracert 10.2.34.1

Tracing route to 10.2.34.1 over a maximum

  1     1 ms     1 ms     1 ms  10.2.34.1
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riazambalathAuthor Commented:
tried adding static route also in isa..........................
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riazambalathAuthor Commented:
we have a cisco 4506 catalyst switch also...
COnfigured with vlan routing.......
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chakkoCommented:
Please go to the old server and type    ipconfig /all

post the results

on the new server do the same and post the results.

please let the IP information (don't change it) otherwise, how can I help
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riazambalathAuthor Commented:
ok...I will do it.....

i did not change any ip configurations all same...

got vlans starting from

10.2.10 to 10.2.130.....

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riazambalathAuthor Commented:
OK...

more clear info...

Core switch....ip is 10.2.32.1

Conf in core switch

vlan 10
ip address 10.2.10.1 255.255.255.0......
ip helper 10.2.32.12

vlan20
ip helper 10.2.32.12

vlan30
ip helper 10.2.32.12

vlan32
no ip helper defined

vlan34
ip helper 10.2.32.12

vlan40
ip helper 10.2.32.12

vlan50
ip helper 10.2.32.12

vlan60
ip helper 10.2.32.12

vlan70
ip helper 10.2.32.12

vlan80
ip helper 10.2.32.12

vlan90
ip helper 10.2.32.12

vlan100
ip helper 10.2.32.12

vlan110
ip helper 10.2.32.12

vlan120
ip helper 10.2.32.12

vlan130
ip helper 10.2.32.12

10.2.32.12 is the DHCP Server

through the dhcp we assign 10.2.32.21(TMG) as the gateway.....

after that 10.2.32. network is working....all other vlans no......



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chakkoCommented:
Your setup looks 'complex'.  Do you have a Networking person or admin?  They should look into the switch VLAN configuration and routing.

My guess is it's a routing problem still.

I think I would need a lot more information so I can't help much more.
Perhaps another expert can zero in on the problem faster and help.
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riazambalathAuthor Commented:
i have an entry in my core switch 0.0.0.0 0.0.0.0 10.2.32.3

10.2.32.3 is the pix

shall i edit it
 0.0.0.0 0.0.0.0 10.2.32.21

10.2.32.21 is ISA TMG
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chakkoCommented:

if that is the only entry in your switch then I would try to change that value to the to TMG and see if it makes a difference.
if it doesn't help then revert to the 10.2.32.3 value.

If the only change you are making to the system is the DHCP server and everything was working before then the switch should already be configured properly.  But try changing the value, you can change it back if needed.

you only provide bits and pieces of information, so can only suggest to keep playing / adjusting settings till you get lucky.
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riazambalathAuthor Commented:
Thank you very much for all the support guys...

I figured out the problem and i must say,i admit too all the comments from u guys made me come up with a successful solution at last...

First of all,

all the vlan information and inter vlan routinf info is on the core switch and the core switch was pointing to the pix firewall...so it was like TMG was not having any role...

so what i did is,

i edited to the core switch info

0.0.0.0 0.0.0.0 10.2.32.3

10.2.32.3 is my pix

with

0.0.0.0 0.0.0.0 10.2.32.21

10.2.32.21....

and i found the internet and website blocking is working fine with the 32 subnet...and i understood that it is because it is the subnet where all the servers exists....

Then i tried added all the other subnets to the internal network of tmg and added static route for them....

and...and yeah here u go...

it worked.......

and again

thanks for all u guys for the support.....
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chakkoCommented:
My last post said to try and edit the routing for the ISA TMG, which he says solved the problem.
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_alias99Commented:
Closing according to the Author's original request, per Zone Advisor's review.

_alias99
Community Support Moderator
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