problem with dhcp service in packet tracer

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hey all of you !! i have a problem with my testlab in packet tracer . i installed dhcp on a r router in packet tracer . i get an ip address for my client, for defaultgateway,subnetmask, but no ip for dns server .

commands i used in ios:

#configure terminal
(config)ip dhcp pool p3
(dchp-config)#network 192.168.5.0 255.255.255.0
(dhcp-config)#default-router 192.168.5.1
(dhcp-config)#dns-server 192.168.3.10
(dhcp-config)#exit
(config)#ip dhcp exclude 192.168.5.2 192.168.5.15
ctrl z
%SYS-5-CONFIG_I: Configured from console by console


you can download my testlab from 2shared server with this url:
http://www.2shared.com/file/wH21ar6p/vervolg_op_oef_op_extended_acl.html

 

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I understand you use these virtual PCs from PT?? Have you tried to /release&/renew??

 

yup and it didn t work . any other possible solution ??

 

DHCP helper?? How these PCs are connected to DHCP machine??

 

#configure terminal
(config)ip dhcp pool p3
(dchp-config)#network 192.168.5.0 255.255.255.0
(dhcp-config)#default-router 192.168.5.1
(dhcp-config)#dns-server 192.168.3.10
(dhcp-config)#exit
(config)#ip dhcp exclude 192.168.5.2 192.168.5.15
ctrl z
%SYS-5-CONFIG_I: Configured from console by console

this is how i configuret the router of my lanfragment

 

That's fine. Are these PCs directly connected to Ethernet interfaces on router or they going via something else??

 

no theres a switch between the end devices and the router .all connected with thaight trough .

 

Just for testing - can you please use different DNS. Try 8.8.8.8 f.e. and see if that's makes any difference. It should not however I have seen many things...

 

try taking out pool p1

also why do you have ip helper addresses on those interfaces? wouldn't think that would be needed because those dhcp requests don't need to be forwarded - the machines are connected to the subnet where the dhcp service is located.

 

Where do you see DHCP helper?? I can not see it unless it is not present only in configs shown...

If there is DHCP helper you obviously right. That was the reason I was asking about way PCs are connected up to the router...

 

Here is part of the config for router 5 which I assume is what he is looking at:

hostname the
!
!
!
!
ip dhcp excluded-address 192.168.5.1 192.168.5.10
ip dhcp excluded-address 192.168.5.2 192.168.5.15
!
ip dhcp pool p1
network 192.168.5.0 255.255.255.0
default-router 192.168.5.1
ip dhcp pool p3
network 192.168.5.0 255.255.255.0
default-router 192.168.5.1
dns-server 192.168.5.20
!
!
!
!
!
!
!
ip name-server 0.0.0.0
!
!
!
!
!
!
interface FastEthernet0/0
ip address 192.168.5.1 255.255.255.0
ip helper-address 192.168.1.2
duplex full
speed auto
!
interface Serial0/0
ip address 192.168.4.1 255.255.255.0
ip helper-address 192.168.1.2
ip helper-address 192.168.3.6
tx-ring-limit 1
clock rate 9600
!
interface Serial0/1
ip address 192.168.6.1 255.255.255.0
ip helper-address 192.168.1.2
ip helper-address 192.168.3.6
tx-ring-limit 1
!
router rip
network 192.168.1.0
network 192.168.3.0
!
ip classless
ip route 192.168.3.0 255.255.255.0 192.168.4.2
ip route 192.168.1.0 255.255.255.0 192.168.6.2
ip route 192.168.3.0 255.255.255.0 192.168.6.2
ip route 192.168.1.0 255.255.255.0 192.168.4.2
ip route 192.168.7.0 255.255.255.0 192.168.6.2
ip route 192.168.8.0 255.255.255.0 192.168.6.2
ip route 192.168.9.0 255.255.255.0 192.168.6.2
ip route 192.168.9.0 255.255.255.0 192.168.4.2
ip route 192.168.8.0 255.255.255.0 192.168.4.2
ip route 192.168.7.0 255.255.255.0 192.168.4.2
!
!


looks like to me there are a number of incorrect or unnecessary commands that have been entered. but if he wants the PC's on the 192.168.5.0 network to get the DNS settgins from dhcp - just enter the command: no ip dhcp pool p1

Also what is doing DHCP for the 192.168.1.0 and 192.168.3.0 networks? as far as I can tell DHCP shouldn't be working for those networks but it is????

 

You're right. IP helper needs to be set up ONLY if we forwarding DHCP requests beyond local VLAN. I have no PacketTracer installed so I made my assumptions only on configs shown. My mistake.

There should be also only one DHCP helper address per interface/VLAN. Using more is theoretically possible for redundancy but needs to be set up really well with excluded ranges etc.

 

this is the startup-conf now, and i still get 0.0.0.0 for def
version 12.2
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname the
!
!
!
!
!
!
!
!
!
!
ip name-server 0.0.0.0
!
!
!
!
!
!
interface FastEthernet0/0
ip address 192.168.5.1 255.255.255.0

duplex full
speed auto
!
interface Serial0/0
ip address 192.168.4.1 255.255.255.0
wp-config.php.
tx-ring-limit 1
clock rate 9600
!
interface Serial0/1
ip address 192.168.6.1 255.255.255.0
ip helper-address 192.168.1.2
ip helper-address 192.168.3.6
tx-ring-limit 1
!

!
ip classless
ip route 192.168.3.0 255.255.255.0 192.168.4.2
ip route 192.168.1.0 255.255.255.0 192.168.6.2
ip route 192.168.3.0 255.255.255.0 192.168.6.2
ip route 192.168.1.0 255.255.255.0 192.168.4.2
ip route 192.168.7.0 255.255.255.0 192.168.6.2
ip route 192.168.8.0 255.255.255.0 192.168.6.2
ip route 192.168.9.0 255.255.255.0 192.168.6.2
ip route 192.168.9.0 255.255.255.0 192.168.4.2
ip route 192.168.8.0 255.255.255.0 192.168.4.2
ip route 192.168.7.0 255.255.255.0 192.168.4.2
!
!
!
ip dhcp excluded-address 192.168.5.1 192.168.5.10


ip dhcp pool p3
network 192.168.5.0 255.255.255.0
default-router 192.168.5.1
dns-server 8.8.8.8
!
!
!
!
!
line con 0
line vty 0 4
login
!
!
!
end

ault and dns-server

 

on router 4 and 5 i entered the command "no ip dhcp pool p"x" . and i stil dont get a dns address on the 192.168.5.0 network . is there someone ho has some input ??

 

no one ?

 

this is the startup-conf now, and i still get 0.0.0.0 for default and dns-server
version 12.2
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname the
!
!
!
!
!
!
!
!
!
!
ip name-server 0.0.0.0
!
!
!
!
!
!
interface FastEthernet0/0
ip address 192.168.5.1 255.255.255.0

duplex full
speed auto
!
interface Serial0/0
ip address 192.168.4.1 255.255.255.0
wp-config.php.
tx-ring-limit 1
clock rate 9600
!
interface Serial0/1
ip address 192.168.6.1 255.255.255.0
ip helper-address 192.168.1.2
ip helper-address 192.168.3.6
tx-ring-limit 1
!

!
ip classless
ip route 192.168.3.0 255.255.255.0 192.168.4.2
ip route 192.168.1.0 255.255.255.0 192.168.6.2
ip route 192.168.3.0 255.255.255.0 192.168.6.2
ip route 192.168.1.0 255.255.255.0 192.168.4.2
ip route 192.168.7.0 255.255.255.0 192.168.6.2
ip route 192.168.8.0 255.255.255.0 192.168.6.2
ip route 192.168.9.0 255.255.255.0 192.168.6.2
ip route 192.168.9.0 255.255.255.0 192.168.4.2
ip route 192.168.8.0 255.255.255.0 192.168.4.2
ip route 192.168.7.0 255.255.255.0 192.168.4.2
!
!
!
ip dhcp excluded-address 192.168.5.1 192.168.5.10


ip dhcp pool p3
network 192.168.5.0 255.255.255.0
default-router 192.168.5.1
dns-server 8.8.8.8
!
!
!
!
!
line con 0
line vty 0 4
login
!
!
!
end

 

ok problem solved . the problem whas that in the startup conf there were ip helper commads id din't saw en so din't erase and that there whas anonther dhcp server on the same segment where i installed dhcp on te router . i deleted the server and rebooted the router and finaly there whas my ip address of my dns . thanx melhiore and host 1976 !