Cisco – Juniper with multiple DHCP pool connected to Cisco switch

ciscojunipersrx

Newbie question:

In our law office we have the following setup: Juniper SRX connected to Cisco L3 switch via trunk port.

Cisco switch has:

VLAN 5 range: 10.4.0.10 – 250 /24
VLAN 6 range: 10.5.0.10 – 250 /24

I want to setup DHCP pool on the Juniper side while keeping those VLANs in mind:

set system services dhcp pool 10.4.0.0/24 address-range low 10.4.0.10
set system services dhcp pool 10.4.0.0/24 address-range high 10.4.0.250
set system services dhcp pool 10.5.0.0/24 address-range low 10.5.0.10
set system services dhcp pool 10.5.0.0/24 address-range high 10.5.0.250

What would be the IP address of the router assigned to clients for the DHCP pool?

set system services dhcp pool 10.4.0.0/24 router ???
set system services dhcp pool 10.5.0.0/24 router ???

Am I even on the right track?
Any other suggestions or something to keep in mind?

Thank you in advance.

Best Answer

Yes, you're on the right page. You need to start by creating the vlans and setting the interfaces on the SRX. The router will be the IP of the Juniper on that vlan.

Create Vlans

set vlans marketing vlan-id 5 set vlans finance vlan-id 6 commit

Decide which interfaces to use

[edit interfaces ge-0/0/3] set unit 0 family ethernet-switching vlan members marketing finance (you might need to separate marketing and finance into two commands or use a comma between. Not sure....) commit

Create layer3 interface for each vlan

set interface vlan unit 5 family inet address 10.4.0.1/24 (assuming .1 is what you want the SRX to be) set interface vlan unit 6 family inet address 10.5.0.1/24

Finish dhcp pool config

set system serivces dhcp pool 10.4.0.0/24 router 10.4.0.1 (assuming this is what you picked above to be the SRX) set vlan marketing l3-interface vlan.5 set system serivces dhcp pool 10.5.0.0/24 router 10.5.0.1 (assuming this is what you picked above to be the SRX) set vlan marketing l3-interface vlan.6

more info: http://www.mustbegeek.com/configure-dhcp-server-for-multiple-vlans-in-junos/

Related Solutions

Cisco – VLAN trunking between Juniper EX -> Cisco Catalyst -> and Cisco Router

You stated that ports 3 and 42 were configured on the Catalyst switch, but then provided configurations for ports 46 and 48. The configuration you posted for port 46 should be applied to port 3 that connects to the EX2200. Your router's connection is unchanged, so hopefully we can assume that configuration is fine.

Now, on the EX2200, the following lines of code would be appropriate to do the following:

ge-0/0/0 - trunk allowing the same vlans as defined above on port 46

ge-0/0/6 - access port on VLAN80

set vlans vlan80 vlan-id 80
set vlans vlan82 vlan-id 82
set vlans vlan83 vlan-id 83
set vlans vlan93 vlan-id 93
set vlans vlan289 vlan-id 289
set interfaces ge-0/0/0 description uplink-to-catalyst 
set interfaces ge-0/0/0 unit 0 family ethernet-switching port-mode trunk
set interfaces ge-0/0/0 unit 0 family ethernet-switching vlan members vlan80
set interfaces ge-0/0/0 unit 0 family ethernet-switching vlan members vlan82
set interfaces ge-0/0/0 unit 0 family ethernet-switching vlan members vlan83
set interfaces ge-0/0/0 unit 0 family ethernet-switching vlan members vlan93
set interfaces ge-0/0/0 unit 0 family ethernet-switching vlan members vlan289
set interfaces ge-0/0/6 unit 0 family ethernet-switching port-mode access
set interfaces ge-0/0/6 unit 0 family ethernet-switching vlan members vlan80

Some other suggestions for you:

1) Turn on LLDP on your switch so you can do a show lldp neighbors and see where your connections go.

2) Don't use RSTP for spanning tree on the juniper switch, it doesn't play nice with Cisco that well, use VSTP instead. If you end up with a ton of vlans, you might even need to use MSTP.

3) Turn off chassis alarm for the management ethernet if you're not using it.

On the EX2200:

delete protocols rstp
set protocols vstp vlan all bridge-priority 4k
set protocols lldp interface all
set chassis alarm management-ethernet link-down ignore

On the Catalyst (if it supports it)

lldp run

Cisco – Is it possible to configure trunking between a NetGear Switch and a Cisco Router

i'm not very familiar with netgear devices. the config seems do be similar to HP Switches. You had to set the Interfaces Tagged or Untagged for the VLAN IDs. Example Port1 is connected to the Router:

set vlan1 UNTAGGED on Port 1 (it's the native Vlan; dot1q Frames are send in the native Vlan)
set all other Vlans you want to transport on this interface TAGGED on Port1

This is different to Cisco Trunks you had to specify each VLan you want to transport on the Trunk Link. I configured a few Trunks between Cisco and HP and this is the way how it works.

Have a look at:

http://documentation.netgear.com/gs108t/enu/202-10337-01/GS108T_UM-10-3.html