Network Setup Problem

[luizsusin]

Hello everyone
Sorry if this is the wrong section, I wasn’t quite sure.

I’m currently trying to setup a FOG environment with 11 computers. They’re all connected to a D-Link xStack DGS-3120-24TC Switch which I don’t have access. All the computers have its own world-visible IP.
I’m running Ubuntu 16.04 LTS and FOG Project 1.5.7.1. The computers are running Windows 10.
I can ping the machines (using Bonjour (Avahi)), so they’re visible to me.

I have used FOG before, but it’s been almost a couple of years. Back in that time, I’ve used Fog’s DHCP server, but now we have this switch so I don’t know how to proceed. Also, the computers can’t find the iPXE server.
I have worked with network setup before, but now, I’m completely lost. I don’t know if I have to setup a DHCP server (even though the Switch is managing it), a ProxyDHCP or something like that.

I appreciate any answer that can guide me forward.
Thanks!

[Sebastian Roth]

@luizsusin said:

I don’t know if I have to setup a DHCP server (even though the Switch is managing it), a ProxyDHCP or something like that.

Usually a switch does not provide DHCP. I had a quick look at the manual of that switch and it does have some fancy stuff like “DHCP Server Screening” which I have not seen before. But as far as I get it this is only the switch listening to DHCP server packet and filtering those. Don’t think that switch really can function as DHCP server.

All the computers have its own world-visible IP.

Do they get those IPs via DHCP or are they manually set? Which DHCP server is handing out the IPs?

[george1421]

@luizsusin said in Network Setup Problem:

I don’t know if I have to setup a DHCP server (even though the Switch is managing it), a ProxyDHCP or something like that.

A quick way to check about your dhcp server is to (on a windows computer) open a command window and key in ipconfig /all then look in the setting for the ethernet adapter you should see a listing for a dhcp server. Tell us what kind of device that is so we can help you with the next steps.

[luizsusin]

@george1421 said:

A quick way to check about your dhcp server is to (on a windows computer) open a command window and key in ipconfig /all then look in the setting for the ethernet adapter you should see a listing for a dhcp server. Tell us what kind of device that is so we can help you with the next steps.

Absolutely! I don’t know how I missed this detail at first sight. I’ve found out that the computers are, in fact, connected to a remote DHCP server.

@Sebastian-Roth said:

Usually a switch does not provide DHCP. I had a quick look at the manual of that switch and it does have some fancy stuff like “DHCP Server Screening” which I have not seen before. But as far as I get it this is only the switch listening to DHCP server packet and filtering those. Don’t think that switch really can function as DHCP server.

Yes, that was what was making me confused too, specially since I have no access or control over this switch (and neither I have worked with managed switches before). But you’re right, they usually don’t provide DHCP and that also applies to this case, since ipconfig /all showed me that there’s a remote DHCP server.

Do they get those IPs via DHCP or are they manually set? Which DHCP server is handing out the IPs?

I’m afraid I can’t answer this question with total certainty. The ipconfig showed me that they have a concession expiration time, so I’m guessing that they’re being handled by that remote DHCP server.

Since there’s a DHCP Server already set, is it possible to set up a ProxyDHCP in this environment I’ve described? For what I’ve read, the ProxyDHCP was meant, possibily, to fulfill this exact problem I’m having, where I have no access to the DHCP infrastructure.

[george1421]

@luizsusin Yes a proxy dhcp service will work here.

I have a tutorial for that: https://forums.fogproject.org/topic/12796/installing-dnsmasq-on-your-fog-server

It should take you less than 15 minutes to set it up. Make sure you use my config file exactly and update it with your fog server’s IP address.

Now I have to say, ProxyDHCP only works by default when the pxe booting client is on the same subnet as the dnsmasq (ProxyDHCP) server. If your clients are on a different subnet then you will need to update your subnet router’s settings.

[luizsusin]

@george1421 Worked flawlessly! Thank you and @Sebastian-Roth so much for the help!