DHCP on multiple interfaces
-
@ddanielpala said in DHCP on multiple interfaces:
Totally agreed regarding the separation of networks. At-least have a separate network for all personal devices.
Absolutely!
So what if I have an IP in OPT1 interface and allow that as the default gw for OPT1 DHCP.
I don't get that ;) Can you make an example?
-
@JeGr So,
For opt1 interace which is 192.168.5.0/24, interface static IP would be 192.168.5.1 (pfsense -> interfaces) and then for DHCP
(pfsense -> services -> dhcp server -> go to opt1 interface)
select Enable DHCP server and configure its default gw as 192.168.5.1 as the GW.
Then ISP won't know who is this new DHCP server as it only knows DHCP server is LAN, am I right? -
So your problem is your using 192.168.0/24 and you need more IPs in this network.. But your problem is your already using .1 and .2, etc. So you can not just expand the network to a /23 or /22 for example because it would overlap your other networks.
The proper solution then is to change the network to say 192.168.6/23 or some other range completely..
If your devices are all dhcp changing the lan network to 192.168.6/23 would be simple as your devices getting new IP via dhcp.. After you change it.
If you need more than a /23, then use say 192.168.8/22
-
@ddanielpala said in DHCP on multiple interfaces:
Then ISP won't know who is this new DHCP server as it only knows DHCP server is LAN, am I right?
The ISP doesn't know anything about your internal networks as you're NATting them outbound to your WAN IP anyway. So if you're coming from .5.x or .0.x you'll get mapped by pfSense to your WAN IP either way.
-
@JeGr So in that case, having a static IP on OPT1 and make that Ip as the default GW for DHCP under OPT1 should solve the issue, correct?
-
You can create as many networks as you want.. If you want to put some of the devices that are currently on your lan network, on some other opt1 network sure that works..
-
@johnpoz Thanks. So pfsense will use both dhcp services(running on LAN and OPT1) allocate IP addresses accordingly?
-
Yeah lan devices will get IPs from the lan dhcp pool, and devices in the opt1 network will be getting ips from that pool.
Are none of your other networks using dhcp?
Not understanding what the concern is here.. You clearly are running multiple networks, how is it you think you can only run 1 dhcpd pool?
Your not wanting to run 2 different networks on the same L2 are you??
-
@johnpoz Other networks are wired. Not in DHCP
-
@ddanielpala said in DHCP on multiple interfaces:
Other networks are wired. Not in DHCP
Huh?? What does wired or not have to do with dhcp? Your saying those other networks are all assigned static on the devices? Why? How many devices?
-
Forget about other networks. What I am trying to achieve is to have two DHCP server on two different networks for clients to connect. Thanks.
-
@ddanielpala said in DHCP on multiple interfaces:
What I am trying to achieve is to have two DHCP server on two different networks for clients to connect.
You can configure a DHCP server on every interface.
-
Yeah you could have 100's, shoot prob 1000s - depending on the umph of your hardware of networks and dhcp running on all of them.. I'm just a bit confused to how that is even a question.. Pfsense would be pretty freaking crappy if you could only run dhcpd on 1 network at a time ;) hehehe
So yeah, you can run multiple networks with dhcpd on any or all of them if you want.. Just click the little enable dhcp check box on the interface in the dhcp server section.
What you can not do, and people complain about it is run dhcpd and a dhcp relay.. You can either relay or be dhcp server.. You can not do both things at the same time, even on different networks.
-
@johnpoz Yes, so just thinking, if i have two such dhcp services running, will a personal device that connects to the wifi network get IP from second dhcp service that running on second interface. What changes need to be done to make that work.
-
Huh... You said these would be different networks..
Please do not trying and run multiple layer 3 networks on the same Layer 2 network... That is just borked and cause you all kinds of issues.. Especially if any of these devices need to talk to each other..
If this is a single layer 2 network.. Then you NEED to change its ip range so you can increase network size to be appropriate for number of devices.. /23 or /22 - I really wouldn't put more than say a /22 on the same network.. Especially if they are chatty little window boxes that love to send out craptons of broadcasts and multicast..
-
@johnpoz I understand.
By network I meant two different subnets -
That is implied its 2 different L2 networks.. You do not run multiple L3 networks on the same L2 - its BORKED!! especially with 2 different dhcp servers..
Do what I suggested and move the IP range to something new so you can use a /22 or /23 network if you need more IPs on the same network.
edit: Don't tell me the other networks you mention are all on the same L2??? That is why your not running dhcp on them???
-
@johnpoz Yes, I think that's the right approach. Thank you.
Like I said, we have an unused interface OPT1, so I can just disable DHCP on LAN and enable DHCP on OPT1. We do have around 10-15 static mappings which then need to add it to the new DHCP interface.
After that, we will work on organizing our entire networks in a more proper way as @JeGr suggested.
Thank you -
So this is just one big flat network with multiple layer 3 networks on it.. OMG.. what a cluster..
Do you have switches that support vlans? Do you have multiple switches?
If all you want is 1 big network, then do that - there is no reason to run multiple layer 3 networks if all you have is one L2.. You are not actually isolating anything from talking to each other if al your doing is using different IP schemes for different clients. So you might as well just put them on 1 network.
To properly segment clients, you need to do it at layer 2 first..
