[SOLVED] DHCP not working with VLAN setup

Routers
1

Hello,
just put a new Route 10 in operation and testing it out.

I have 3 VLANs in my network, 99, 10 and 20 , so I simply created the same 3 VLANs in the Route 10 site and put all of them on the trunk port connected to the main switch.

image
image600×612 30.3 KB

Each VLAN has the same DHCP settings (with the exception of the vlan subnet having the second digit identical to the vlan tag):

image
image662×734 34.1 KB

The problem is that I cannot get an IP address through DHCP from any of my clients; I know that routing is working fine as I can reach the internet and SSH to the router address from devices in any VLAN by setting ip/gateway manually.

Running the latest software version (1.3k).

Any suggestion as to what could be wrong? Used the same setup previously on RouterOS.

2

One thing I know is “Color/Group” is not working on Rout10 right now. If you have that set, make sure to change that back to black. Also, there has to be one untagged VLAN on the trunk for the switch to get an IP and pass traffic… do you have DHCP set on a VLAN 1 as well?

3

There’s no untagged VLAN 1, but traffic is passing through as I can reach the internet and even SSH into the router from any vlan (using the gateway VLAN address, e.g. 192.168.99.1), just DHCP isn’t working properly for some reason.

4

So with the family to bed I had time to swap again the tik with the route 10 :slight_smile:

Found the issue after looking at the raw config files, basically I set a lease reservation with a name containing spaces, thinking that this name was only for reference purposes:

image
image596×328 17.1 KB

However it turns out that these names are written as is to dnsmasq.conf , which then won’t start:

dhcp-host=6c:7e:67:cb:77:d8,192.168.20.100,TEST HOSTNAME

Nov  3 23:43:10 HappyTravels2 daemon.alert cfg: Found dnsmasq config changes, applying.
Nov  3 23:43:10 HappyTravels2 daemon.alert cfg: run "/etc/init.d/dnsmasq reload"
Nov  3 23:43:10 HappyTravels2 daemon.crit dnsmasq[1177]: bad DHCP host name at line 45 of /var/etc/dnsmasq.conf.cfg01411c
Nov  3 23:43:10 HappyTravels2 daemon.crit dnsmasq[1177]: FAILED to start up

Now I fixed the names and DHCP started working as expected, however I would strongly suggest to make sure that:

  • The UI does not allow entering invalid values
  • If a critical service does not start, some notification is shown in the UI or sent to the account holder
5

Good find! I do have some good news, the naming issue is already in the fix list for the next firmware update that is coming. I was actually the one that found that bug… and I didn’t think to ask you :(. Sorry about the delay on that one!

6

Great to know it’s already in the backlog, it was actually fun to have an excuse to ssh into the Route10 and see what’s running behind the scenes :slight_smile: