Vlans & DHCP implementation

[ASVLANS]

Hi everyone,

We are expecting to introduce a new router on our network wich will be compose by 2x OS6850-U24X. In the same way, we need to set several VLANS for reduce our broadcast.

I will try to be clear. At this time we are on a testlab which compose by one 6850 as a router. Also, we had configure 2 user computer and 1 DHCP server. After that we have a DSL router to go on the web.

Let's get start with the configurtion on the 6850 :

vlan 1 enable name "VLAN 1"
vlan 100 enable name "Vlan_wifi"
vlan 100 port default 1/2
vlan 100 port default 1/12
vlan 172 enable name "Vlan_ip_fixe"
vlan 172 port default 1/6
vlan 172 port default 1/7
vlan 172 port default 1/8
vlan 172 port default 1/16
vlan 200 enable name "Vlan_Data"
vlan 200 port default 1/3
vlan 200 port default 1/13
vlan 300 enable name "Vlan_VOIP"
vlan 300 port default 1/4
vlan 300 port default 1/14
vlan 400 enable name "Vlan_admin"
vlan 400 port default 1/5
vlan 400 port default 1/15
ip interface dhcp-client vlan 1 ifindex 1
ip interface "vlan-200" address 135.118.212.1 mask 255.255.252.0 vlan 200 ifindex 2
ip interface "vlan-300" address 135.118.210.1 mask 255.255.254.0 vlan 300 ifindex 3
ip interface "vlan-100" address 135.118.208.129 mask 255.255.255.128 vlan 100 ifindex 4
ip interface "vlan-400" address 135.118.208.1 mask 255.255.255.224 vlan 400 ifindex 5
ip interface "vlan-172" address 172.25.140.1 mask 255.255.248.0 vlan 172 ifindex 6
ip router primary-address 192.168.1.1
vlan 100 802.1q 1/1
vlan 172 802.1q 1/1
vlan 200 802.1q 1/1
vlan 300 802.1q 1/1
vlan 400 802.1q 1/1
ip static-route 0.0.0.0 mask 0.0.0.0 gateway 192.168.1.1

We possess two IP => 172.25.140. & 135.118.208.
The communication between users in the same VLAN looks fine.

Anyway we have trouble to set the DHCP pool in once interface wich option should we set ?

On the other side we have integrate on the linksys DSL the route for each vlan but it don't works... we also try to make a router primary address on the 6850 and open the route on linksys.

Sorry for grammatical mistakes (isn't my born language)
Thanks

[one6f]

Hi,
1.first regarding your problem. I understand you use 1 external DHCP server (not implemented in the switch) for all your vlans.
Then you need probably an ip helper entry for each vlan with dhcp clients. Such as:
Consult Configuring DHCP in Network Configuration Guide for setting DHCP Relay.

Code: Select all

ip helper per-vlan only  
ip helper address 10.10.0.15 vlan 10 
ip helper address 10.11.0.15 vlan 11 
ip helper address 10.66.0.28 vlan  124 
ip helper forward delay 0 

2. You have configured i.e. that any traffic for anywhere go via the next hop 192.168.1.1 that is your router primary-address but not exit interface (to DSL router).
3. It's strange that you use a public internet addresses (135.118.x.x) in your intern network.
First of all, I suggest that you draw a plan or concept with all your requirements (switches, router with links, server, ip addresses, net-masks....), then it will be easier to configure all that;)

[ASVLANS]

Thanks for your reply. Our problem came from our IP address which wasn't on the same IP network like 192.168...
And due to this, the ip primary address was wrong too.

Your iphelper commands help us very much!

All of our configuration works now. Now we will test with an second DHCP server for vlan 2 (because ou DHCP is a computer in lab)

Maybe someone know how configure the dhcp server (windows server 2008 R2) with one linked network's interface.

Thanks again.
Best regards

[krzysioD]

Search for those: it may have some old command but, it's basic ALU switch config for AVA.

AVA Configuration with Mobile Tag Feature ( Tip #2050 )
Product OmniSwitch Product
Feature Group Mobility
Technology Bridging
Attachments 2050_AVA_and_Mobile_Tag_on_6600.pdf
Date Submitted 2005-04-14


Automatic Vlan Assignment Configuration Example ( Tip #2062 )
Product PCX-VoIP
Feature N/A
Technology VoIP Gateway
Attachments 2062_AVA_Configuration_example.pdf
Date Submitted 2005-05-02

TC601

TIP #4451