Fresh VM and Fog 1.2.0 install having issues with iPXE boot

jcook

I took a packet capture from the time the client booted to a minute or so after it asked for me to put in the tftp IP. The mac address for the client is
78:45:c4:0e:5d:a3 and fog server is 172.18.164.6 it that will help to filter. If more info would help interpret the cap let me know.

https://drive.google.com/file/d/0BxsOsMJZGNhYWklZNldIUWpCcU0/view?usp=sharing

jcook

Also as a test I set up a new router and move the fog and client to it on a dumb switch and everything seems to be working. I was a able to get to the fog boot screen so its must be something with network I just don’t know enough to figure it out. I am going to see if I can get STP disabled on the network to see if that does the trick.

Sebastian Roth

@jcook Your FOG server (172.18.164.6) and the client (172.18.165.245) are on two different subnets (netmask being 255.255.255.0). This does not have to be an issue but I am wondering if you are aware of the fact that client and FOG server need use a gateway to talk to each other.

What kind of DHCP server do you use? I see option 66 and 67 (seem fine) but the DHCP server does not set those options in the DHCP header (next-server and filename). Not sure if this is causing the “Please enter tftp server” message because iPXE does not find option 66 in the DHCP answers - kind of strange… not sure about that.

Let me guess - you captured the packets from a different host in your network. This is why we see the DHCP conversation but no TFTP packets! Can you please do it again but capture the packets on the FOG server. Either use wireshark if you have GUI installed. Or install tcpdump and run it like this tcpdump -w /tmp/bootup.pcap port 67 or port 68 or port 69 or port 80 (just leave the command, boot your client till you get the error/hang and then stop tcpdump with ctrl+c and upload the file /tmp/bootup.pcap to the forum)

jcook

Our DHCP is handled by a Adtran Netvanta 3140. I think at first the clients on the 165 subnet were trying to use 172.18.165.1 as the tftp server so a rule is in place to forward it to fog (172.18.164.6). Clients could get to the fog boot screen after those changes on old fog server running 0.32 so i thought we were all good.

You were correct about the previous cap, I’m a networking novice. Here is the capture file

0_1460744849002_bootup.pcap

Sebastian Roth

@jcook That’s funny. This time I only see the TFTP but no DHCP traffic…

TFTP traffic looks ok but the HTTP request for boot.php is being terminated (reset flag) by the client just a few micro seconds before the HTTP server would send it’s answer?!? Maybe that caused by some kind of HTTP filter on the gateway?

george1421

@Sebastian-Roth I’ve only loosely been following this (sorry spring fever today), but remember the tcpdump program will only see dhcp traffic if its in the same broadcast domain (subnet) as the client computer. Once dhcp hits the router and dhcp-helper service it goes unicast.

jcook

It is something to do with a content filter we have. Its blocking the http traffic to the fog server and i will fix that. I still had to put in the tftp server IP. The router has a place to give the a tftp IP and setup option 66. I will try a few different ways and let you know. I feel dumb for totally forgetting about the content filter >_< doh!

Sebastian Roth

@jcook Maybe you can post a screenshot of the DHCP configuration site so we might be able to help with that as well.

jcook

alt text

The first image is my current config with both options passed. I have also put the fog IP in the “TFTP Server” of the second image. Either way it still asks for the tftp server IP, and once input it now boots to fog.

Here is where a new problems occurs. The fog boot options are only there for a second and I would like to make it just a few seconds longer, but I can load “Fog Configuration” in the web UI. I get a 404 error with the following text
“Not Found
The requested URL /static/index.html was not found on this server.”

jcook

Just an update, I am able to upload and deploy images (once chose the right options for the image lol).

Really the only things that I need to fix now seem to be the TFTP server needing to be input during the boot. I was able to find out the settings that are needed for my Adtran router and switches to TFTP correctly. On the router I had to enable BPDU filter in the Spanning Tree options, then enable edge port mode on the switch ports that have clients. Also make sure your content filter isn’t blocking the Fog server (facepalm). Maybe this can help any one with a similar set up to ours.

george1421

@jcook If you are being questioned about the fog server IP during booting then your dhcp server is not sending out dhcp option 66 {next-server}. On the image you posted, I see a spot for tftp server (which is blank in the picture), did you enter the IP address of the fog server there?

Thinking a bit longer, if you are being prompted for the up address of the FOG server, then the ipxe kernel is making it to the target computer. Can you confirm that you have RSTP or port-fast enabled on the network port that is connected to the target computer? The network port will wink as it transitions between the PXE ROM, and the iPXE kernel. If the port isn’t forwarding (because its still in spanning tree learn mode) the iPXE kernel may not hear the next server reply.

jcook

@george1421 The switches and routers are showing they are in RSTP as far as I can tell. I was reading up on “edge-port mode” for this equipment and it said that “will transition directly in to the forwarding state.” I haven’t put the unmanaged switch between the client and the manage switch again but will see if that helps. I will also add fog to the TFTP field and see if it helps (i think I have before but doesn’t hurt).

I will probably also reach out to my switching support and see if they can help me with option 66 if adding it to the TFTP field doesn’t help.

EDIT: Adding the Fog ip the empty TFTP field didn’t help, also the unmanaged switch between client and core has the same result, still asking for TFTP ip. Is there a way to hard code this somewhere is Fog?

george1421

@jcook said

EDIT: Adding the Fog ip the empty TFTP field didn’t help, also the unmanaged switch between client and core has the same result, still asking for TFTP ip. Is there a way to hard code this somewhere is Fog?

See that information is suppose to come from the second dhcp request from the iPXE kernel. To answer your question, yes you can hard code it in, but you will need to build your own ipxe kernel (not hard at https://rom-o-matic.eu/)

This might get you started https://forums.fogproject.org/topic/6347/usb-boot-bios-client-into-fog-menu

jcook

@george1421 Thanks for the info. I will probably give that a try later, and see how it goes.

I have the option to make the DHCP options be given in either ASCII or as an IP address or hex for that matter. Does is make a difference what I choose?

Sebastian Roth

@jcook said:

I have the option to make the DHCP options be given in either ASCII or as an IP address or hex for that matter. Does is make a difference what I choose?

You can try ASCII instead of IP address but I kind of doubt this will make a difference. But please add another option (number: 60, type: String, value: PXEClient) and see if that helps.

george1421

@jcook If you experience no joy on this we may need to get a pcap file (tcpdump) of the dhcp discovery process to see what is or isn’t being sent. As long as the pxe client and fog server are in the same subnet/vlan its pretty easy to collect.

While this part isn’t specifically a FOG issue, it is one of the more common problems to setup. If you hang in there we can usually help you through this part. While PXE booting is not difficult to setup, there are a few parts that need to be configured in a specific order.

jcook

Fog worked great before so I’m definitely gonna get it working again one way or another. Since our school is fairly small I actually have time over the summer to image computer individual if I need too. At the moment though, I have all the computers on the campus with this Fog server network booting by default. Some of the teachers can handle pressing escape to skip it, so I have to go do it for them. But its a minor inconvenience compared to the power of Fog! I am going to call my switching support and see if they can help me see if the options are being passed. If not I can temporarily move fog to the same sub net and do the tcpdump on it again. If I have to do the capture I will post file.

jcook

I built my own iPXE kernel with this:

#!ipxe

dhcp
set next-server 172.18.164.6
set filename undionly.kpxe
chain tftp://${next-server}/${filename}

Then saved the file to my fog server and updated option 67 to the file name. Also changed owner and group. Boot client and at first it didn’t ask for the IP, but it loops and never loads the Fog menu. I think I can see why its doing it but don’t what change.

Tom Elliott

@jcook That is because you have it looping itself.

It’s ALWAYS going to be loking to get the next-server and filename which is the same you’re telling it to request.

Your ipxe kernel file should be

#!ipxe
dhcp
set next-server 172.18.164.6
chain tftp://${next-server}/default.ipxe

jcook

It still asks me for the IP of the Fog server. This stuff is mostly beyond me but maybe that will help yall out lol.

Fresh VM and Fog 1.2.0 install having issues with iPXE boot

136

11.7k

17.2k

154.7k