TFTP ARP Timeout

Sebastian Roth

@cammykool Sorry but I need to head off now. Time to catch some sleep…

cammykool

67 is set to 10.1.80.1 in DHCP and ubuntu has it set up manually for the same

george1421

@cammykool OK wait a minute. Why does the first picture have a subnet mask of 255.255.0.0 (/16) and the ubuntu server have 255.0.0.0 (/8)

george1421

Also lets confirm what you have exactly configured in your dhcp server. What do you have defined for dhcp option 66 and 67 respectively?

cammykool

@george1421

i noticed in fogsettings it is set to 255.255.0.0. i changed it there.

george1421

@cammykool You also need to change it in the network manager since you are using ubuntu.

Then from the fog server command prompt key in ip addr show and confirm that the subnet mask matches the rest of your network. If it doesn’t reboot the fog server and then confirm.

cammykool

@george1421

thats the winserver config.

cammykool

@george1421 ip addr show is still showing 255.255.255 even after changing in network manager

user@fog:~$ ip addr show
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host
       valid_lft forever preferred_lft forever
2: enp0s25: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether 18:03:73:cf:ab:5a brd ff:ff:ff:ff:ff:ff
    inet 10.1.80.1/8 brd 10.255.255.255 scope global noprefixroute enp0s25
       valid_lft forever preferred_lft forever
    inet6 fe80::7298:8d49:d303:484d/64 scope link noprefixroute
       valid_lft forever preferred_lft forever

george1421

@cammykool Actually if you look after the IP address is /8 or 255.0.0.0. Then reboot the fog server since it may only load at boot time.

edit, maybe you could do sudo ifdown enp0s25 then sudo ifup enp0s25 to avoid the reboot time.

george1421

Understand that fixing the subnet mask may not address the pxe booting problem, but it will fix ARP resolution. The subnet mask controls where the broadcast address is. Two different subnet masks have their broadcast address in different locations so the two clients will have difficulty finding each other.

cammykool

@george1421 it looked to be /8 too before

pxe is still getting 255.255.0.0 at boot

george1421

@cammykool So you updated the network manager application and then either did the ifup/ifdown or reboot and its still set to /8?

The pxe stuff is coming from your dhcp server not the fog server. Your client is still having a problem finding the fog server from your first picture.

cammykool

yes it is. Netowkr manager has always been correct.

cammykool

im working on the guide i was sent initially. boss gave me direct access to the DHCP server

george1421

@cammykool said in TFTP ARP Timeout:

yes it is. Netowkr manager has always been correct.

Ok I think I’m lost here (not surprised since I jumped in late). The subnet mask of /16 255.255.0.0 is coming from your windows dhcp server. That has to be the right subnet mask for your network. Why is the FOG server set to /8 255.0.0.0?

What is the correct subnet mask for your computers? You can open a command windows on your dhcp server and key in ipconfig /all to confirm your subnet mask. The fog server needs to have the same subnetmask as your windows servers.

cammykool

@george1421 huh my windows box is getting 255.255.0.0 too. He gave me the 255.0.0.0 to use. Ill Change it

george1421

@cammykool said in TFTP ARP Timeout:

He gave me the 255.0.0.0 to use

Hmm sounds like someone is being setup for failure right out of the box.

cammykool

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This is the data he gave me to use LMAO

cammykool

Do you think subnet mask could be the issue?

cammykool

user@fog:~$ ip addr show
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host
       valid_lft forever preferred_lft forever
2: enp0s25: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether 18:03:73:cf:ab:5a brd ff:ff:ff:ff:ff:ff
    inet 10.1.80.1/16 brd 10.1.255.255 scope global noprefixroute enp0s25
       valid_lft forever preferred_lft forever
    inet6 fe80::7298:8d49:d303:484d/64 scope link noprefixroute
       valid_lft forever preferred_lft forever

there we go

TFTP ARP Timeout

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