topic Re: DHCP... What Gives... in Switches, Hubs, and Modems

DHCP... What Gives...

psycho.chicken — Tue, 09 Jan 2007 15:40:14 GMT

I'm stuck..

I cant get dhcp to relay...

If i manually set IP's i can ping across vlan's just fine...

If I am on the same switch, and same vlan, i can get an address...
If I am on a different switch, but same vlan... i get nothing...

Different switch different vlan... nothing

Same switch different vlan.. nothing...

I set up all vlan's to use the helper ip and enabled dhcp relay...

what gives...?

Re: DHCP... What Gives...

psycho.chicken — Tue, 09 Jan 2007 15:49:42 GMT

A little more info...

5300 is 10.3.100.200

2650 is 10.3.100.201

i created a vlan100 10.3.100.1

Re: DHCP... What Gives...

Matt Hobbs — Tue, 09 Jan 2007 15:51:27 GMT

What DHCP Server are you using? Is the default gateway on the DHCP server set correctly?

Re: DHCP... What Gives...

psycho.chicken — Tue, 09 Jan 2007 15:53:30 GMT

5403xl

hostname "wa_5406zl_01"
snmp-server contact "Systems"
module 1 type J8702A
module 2 type J8702A
ip routing
snmp-server community "public" Unrestricted
vlan 1
name "DEFAULT_VLAN"
untagged A2-A11,A13-A24,B7-B24
ip address 10.3.100.101 255.255.255.0
tagged A1
no untagged A12,B1-B6
exit
vlan 10
name "vlan10-d"
untagged B1
ip helper-address 10.3.0.70
ip address 10.3.10.1 255.255.255.0
tagged A1
exit
vlan 20
name "vlan20-d"
untagged B2
ip address 10.3.20.1 255.255.255.0
tagged A1
exit
vlan 30
name "vlan30-d"
untagged B3
ip address 10.3.30.1 255.255.255.0
tagged A1
exit
vlan 40
name "vlan40-d"
untagged B4
ip address 10.3.40.1 255.255.255.0
tagged A1
exit
vlan 50
name "vlan50-d"
untagged B5
ip address 10.3.50.1 255.255.255.0
tagged A1
exit
vlan 90
name "vlan90-d"
untagged A12,B6
ip helper-address 10.3.0.70
ip address 10.3.0.200 255.255.255.0
tagged A1
exit
vlan 100
name "vlan100-m"
tagged A1
no ip address
exit
spanning-tree
password manager

--------------------------------

2650

hostname "wa_vlan10_01"
snmp-server contact "systems"
ip default-gateway 10.3.100.200
snmp-server community "public" Unrestricted
vlan 1
name "DEFAULT_VLAN"
untagged 7-48,50
ip address 10.3.100.102 255.255.255.0
tagged 49
no untagged 1-6
exit
vlan 10
name "vlan10-d"
untagged 1
ip address 10.3.10.1 255.255.255.0
ip helper-address 10.3.0.70
tagged 49
exit
vlan 20
name "vlan20-d"
untagged 2
ip address 10.3.20.1 255.255.255.0
tagged 49
exit
vlan 30
name "vlan30-d"
untagged 3
ip address 10.3.30.1 255.255.255.0
tagged 49
exit
vlan 40
name "vlan40-d"
untagged 4
ip address 10.3.40.1 255.255.255.0
tagged 49
exit
vlan 50
name "vlan50-d"
untagged 5
ip address 10.3.50.1 255.255.255.0
tagged 49
exit
vlan 90
name "vlan90-d"
untagged 6
ip address 10.3.0.200 255.255.255.0
ip helper-address 10.3.0.70
tagged 49
exit
spanning-tree
password manager

Re: DHCP... What Gives...

psycho.chicken — Tue, 09 Jan 2007 15:55:55 GMT

dhcp server is a w2k3 box

had scopes of

vlan10
10.3.10.200-250
255.255.255.0
10.3.10.1

vlan20
10.3.20.200-250
255.255.255.0
10.3.20.1

etc...

vlan90
10.3.0.215-225
255.255.255.0
10.3.0.200

dhcp server was set up with
10.3.0.70
255.255.255.0
10.3.0.200

Re: DHCP... What Gives...

Matt Hobbs — Tue, 09 Jan 2007 16:03:31 GMT

You have the same IP addresses configured on your 2600 VLANs... leave only the IP address for the management VLAN, the others do not need an IP address. At the moment you're causing IP conflicts which is probably confusing the DHCP Server.

Also seen a few instances lately where the 5400 just needs to be rebooted for DHCP-Relay to work properly.

Don't forget to assign points along the way to any replies you receive.

Re: DHCP... What Gives...

psycho.chicken — Tue, 09 Jan 2007 17:09:07 GMT

So do i not give my actual hardware a IP address?

What is the proper way to manage the device...

Would i just give the switches IP's in one of the exhisting subnets?

Re: DHCP... What Gives...

psycho.chicken — Tue, 09 Jan 2007 17:17:13 GMT

I'm not seeing the duplicate IP's your talking about...

(I could be blind today...)

Re: DHCP... What Gives...

psycho.chicken — Tue, 09 Jan 2007 17:18:32 GMT

I havebt created a management vlan either...

Re: DHCP... What Gives...

Matt Hobbs — Tue, 09 Jan 2007 17:33:19 GMT

Each of your edge switches only requires one IP address for management. So for your 2600 you had:

vlan 1
name "DEFAULT_VLAN"
untagged 7-48,50
ip address 10.3.100.102 255.255.255.0
tagged 49
no untagged 1-6
exit
vlan 10
name "vlan10-d"
untagged 1
ip address 10.3.10.1 255.255.255.0
ip helper-address 10.3.0.70
tagged 49
exit

Keep the IP address of VLAN1, it's fine since it is different to the 5300. You need to do is remove the IP address on VLAN 10 (which is the same as the IP address on the 5300). You also need to remove those IP addresses on all those other VLANs.

You could also give those VLANs different IP addresses, e.g 10.3.10.2, but there's no need.

Re: DHCP... What Gives...

psycho.chicken — Tue, 09 Jan 2007 17:36:23 GMT

isnt 10.3.10.1 supposed to be given to the vlan, as it's default gateway...

Re: DHCP... What Gives...

psycho.chicken — Tue, 09 Jan 2007 17:40:28 GMT

That IP is coming from me creating the vlans, I gave each vlan an ip...

vlan10 = 10.3.10.1 /24 etc

is this not correct?

Re: DHCP... What Gives...

Matt Hobbs — Tue, 09 Jan 2007 17:44:24 GMT

An IP address has to be unique on the VLAN that it's in. Since you have the same address configured on both switches that is a big no no. The 5300 is doing all your routing so it should be the only one to have those IP addresses.

I would recommend you go through this free self paced course - http://www.hp.com/rnd/training/technical/IPR_foundations.htm

Re: DHCP... What Gives...

psycho.chicken — Tue, 09 Jan 2007 17:51:21 GMT

Dont i create the vlans on both switches?

Re: DHCP... What Gives...

Matt Hobbs — Tue, 09 Jan 2007 17:57:57 GMT

Yes, but you don't give them IP addresses, especially don't give them the same IP address which has been configured on another switch.

On that 2600, you can either do:

2600(config)# vlan 10
2600(vlan-10)# no ip address

or

2600(config)# vlan 10
2600(vlan-10)# ip address 10.3.10.2/24

Repeat for the other VLANs but leave VLAN1 alone, it's okay because it has a different IP address to that of VLAN1 on the 5300.

The first option is how I would do it on the other VLANs(no ip address)

Re: DHCP... What Gives...

psycho.chicken — Tue, 09 Jan 2007 18:05:54 GMT

ok...

I was under the impression that i am creating the vlans on all the switches.

meaning i tell switch 5400-1

vlan10-d 10.3.10.1 /24

tell switch 2

vlan10-d 10.3.10.1

----

Your tellign me to

switch 5400-1

vlan10-d 10.3.10.1

switch 2

vlan10-d 10.3.10.2

switch 3

vlan10-d 10.3.10.3

etc...

So the default gateway on swithces 2,3,4 is still switch 5400... 10.3.10.1

Re: DHCP... What Gives...

Matt Hobbs — Tue, 09 Jan 2007 18:15:15 GMT

That's kind of what I'm telling you but I wouldn't bother putting those IP addresses on for VLAN10,20,30 etc. A VLAN does not have to have an IP address.

This would be config I would base my edge switches on:

hostname "wa_vlan10_01"
snmp-server contact "systems"
ip default-gateway 10.3.100.200
snmp-server community "public" Unrestricted
vlan 1
name "DEFAULT_VLAN"
untagged 7-48,50
ip address 10.3.100.102 255.255.255.0
tagged 49
no untagged 1-6
exit
vlan 10
name "vlan10-d"
untagged 1
tagged 49
exit
vlan 20
name "vlan20-d"
untagged 2
tagged 49
exit
vlan 30
name "vlan30-d"
untagged 3
tagged 49
exit
vlan 40
name "vlan40-d"
untagged 4
tagged 49
exit
vlan 50
name "vlan50-d"
untagged 5
tagged 49
exit
vlan 90
name "vlan90-d"
untagged 6
tagged 49
exit
spanning-tree
password manager

The other edge switches would be the same, except they would each have a different IP addresses in VLAN1

vlan 1
name "DEFAULT_VLAN"
untagged 7-48,50
ip address 10.3.100.103 255.255.255.0
tagged 49
no untagged 1-6
exit

The default gateways will remain pointing to the .1 addresses that is already configured on the 5400. The 5400's configuration is fine the way it is.

Re: DHCP... What Gives...

psycho.chicken — Tue, 09 Jan 2007 18:21:42 GMT

but the default gateway (on client pc's) will still be the 10.3.10.1 etc... that i put into the 5400

SO I AM re-creating the vlan's on the other switches, just not giving them all IP's, just the primary one...

And that could be the management one at that...

I'm gonna reset to factory and try it out.

It makes sence, i just confused myself and programmed too much on the edge switches...

Re: DHCP... What Gives...

psycho.chicken — Tue, 09 Jan 2007 20:00:07 GMT

That was the ticket!

DHCP Relay is working!!

Now everytime i reboot the switch.. all the setting sgo away but the main IP...

Re: DHCP... What Gives...

psycho.chicken — Tue, 09 Jan 2007 20:00:33 GMT

Yes, I did a "write memory"