Ethernet Switching
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Ethernet Switching

DHCP Relay EX4600 with Routing Instances

‎03-05-2018 03:25 PM

I have a pretty straight forward network, however I am using routing-instances (set as virtual router) to route vlans through a central firewall.  As such, I need all of my data vlan clients to be able to get DHCP addresses from my server vlan.  On cisco this was incredibly easy and is  as simple as setting ip helper address on each vlan SVI and it just works.

 

Comparitively, on this EX4600 it appears that there are a TON of dhcp options and configurations.  All I really need to do is make sure clients can get an IP from my windows server.  I just want to be sure I don't miss anything:

 

My config which does work in testing:

 

routing-instances {
    Data {
        instance-type virtual-router;
        interface irb.10;
        interface irb.20;
        interface irb.300;
        routing-options {
            static {
                route 0.0.0.0/0 next-hop 1.1.0.4;
            }
        }
        forwarding-options {
            dhcp-relay {
                server-group {
                    DataVlanDHCP {
                        1.1.11.2;
                    }
                }
                active-server-group DataVlanDHCP;
                group DataRelayGroup {
                    interface irb.10;
                    interface irb.20;
                }
            }
        }

 

 

Questions:

1. Is this the proper method for DHCP relay when using routing-instances or should I be using global config(edit forwarding-options)?

2. Is there anything i should need under the global config in addition to what i have under routing instances?

3. What is the forward-only option?  Should this be set as well?

4 REPLIES 4
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Ethernet Switching

Re: DHCP Relay EX4600 with Routing Instances

‎03-05-2018 04:54 PM
Pl refer following kb.
https://kb.juniper.net/InfoCenter/index?page=content&id=KB30584

under global config, add following to make dhcp working.
set forwarding-options dhcp-relay forward-only-replies


*************************************
HTH.
Accept this as solution if it resolved your issue.
Kudos would be appreciated too.
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Ethernet Switching

Re: DHCP Relay EX4600 with Routing Instances

‎03-05-2018 04:58 PM
Pl refer following kb.
https://kb.juniper.net/InfoCenter/index?page=content&id=KB30584

under global config, add following to make dhcp working.
set forwarding-options dhcp-relay forward-only-replies


*************************************
HTH.
Accept this as solution if it resolved your issue.
Kudos would be appreciated too.
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Ethernet Switching

Re: DHCP Relay EX4600 with Routing Instances

‎03-06-2018 07:07 AM

I see the KB article, but DHCP is already working without the forward-only option set in the config.  All I have done is added the DHCP info to the routing instance as shown, no other options are set.

 

I am more so wondering if there is anything else that is best practice to set and also what the forward-only and forward-only-replies options are doing.  Obviously, my config (at least in my limited testing is working) but maybe I should be including the forward-only options?  I would like to make sure config is good before rolling into production

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Ethernet Switching

Re: DHCP Relay EX4600 with Routing Instances

‎03-06-2018 08:50 AM

As per my experience, not all the scenarios were working without those knobs (forward only and forward only replies).

 

https://www.juniper.net/documentation/en_US/junos/topics/reference/configuration-statement/forward-o...

 

https://www.juniper.net/documentation/en_US/junos/topics/reference/configuration-statement/forward-o...

 

HTH..


*************************************
HTH.
Accept this as solution if it resolved your issue.
Kudos would be appreciated too.
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