Gfilui

I'm building a network with a DHCP server (192.168.201.2), a TFTP/NFS server (192.168.201.3) and other machines that are going to boot from the two, all machines run Ubuntu 16.04.4.

When I turn one on, after post, it successfully receives an IP from the DHCP server, it connects to the TFTP server, loads vmlinuz and initrd.img but when it tries to get the IP again it gives this message:

IP-Config: eth0 hardware address xx:xx:xx:xx:xx:xx mtu 1500 DHCP
IP-Config: no response after 2 secs - giving up
IP-Config: eth0 hardware address xx:xx:xx:xx:xx:xx mtu 1500 DHCP
IP-Config: no response after 3 secs - giving up

and so on.

My configuration

/etc/dhcp/dhcpd.conf

ddns-update-style none;

default-lease-time 600;
max-lease-time 7200;

authoritative;

log-facility local7;

allow booting;
allow bootp;

subnet 192.168.201.0 netmask 255.255.255.0 
 default-lease-time 3600;
 max-lease-time 86400;
 option routers 192.168.201.1;
 option subnet-mask 255.255.255.0;
 option domain-name-servers 208.67.222.222, 8.8.8.8;
 option broadcast-address 192.168.201.255;
 range 192.168.201.3 192.168.201.254;
 filename = "gpxelinux.0";
 next-server 192.168.201.3;


host tftp 
 hardware ethernet xx:xx:xx:xx:xx:xx;
 fixed-address 192.168.201.3;

/tftpboot/pxelinux.cfg/default

MENU LABEL Ubuntu DISKLESS
KERNEL vmlinuz-4.4.0-127-generic
APPEND boot=nfs root=/dev/nfs nfsroot=192.168.201.3:/srv/nfsroot/installer/ default,ro initrd=initrd.img-4.4.0-127-generic ipv6.disable=1 ip=dhcp net.ifnames=0 biosdevname=0

/etc/initramfs-tools/initramfs.conf (on the system on the NFS server)

MODULES=netboot
BUSYBOX=auto
COMPCACHE_SIZE=""
COMPRESS=gzip
DEVICE=eth0
NFSROOT=auto
BOOT=nfs

I found this bug, but it was fixed on klibc - 2.0.4-8ubuntu1.16.04.1, and that's the version I'm running.

I tried running dhcpdump on the DHCP server and I get this:

 TIME: 2018-06-05 11:22:59.057
 IP: 0.0.0.0 (xxx) > 255.255.255.255 (ff:ff:ff:ff:ff:ff)
 OP: 1 (BOOTPREQUEST)
 HTYPE: 1 (Ethernet)
 HLEN: 6
 HOPS: 0
 XID: 4dae1bf8
 SECS: 4
 FLAGS: 7f80
CIADDR: 0.0.0.0
YIADDR: 0.0.0.0
SIADDR: 0.0.0.0
GIADDR: 0.0.0.0
CHADDR: xxx
 SNAME: .
 FNAME: .
OPTION: 53 ( 1) DHCP message type 1 (DHCPDISCOVER)
OPTION: 55 ( 36) Parameter Request List 1 (Subnet mask)
 2 (Time offset)
 3 (Routers)
 4 (Time server)
 5 (Name server)
 6 (DNS server)
 11 (Resource location server)
 12 (Host name)
 13 (Boot file size)
 15 (Domainname)
 16 (Swap server)
 17 (Root path)
 18 (Extensions path)
 22 (Maximum datagram reassembly size)
 23 (Default IP TTL)
 28 (Broadcast address)
 40 (NIS domain)
 41 (NIS servers)
 42 (NTP servers)
 43 (Vendor specific info)
 50 (Request IP address)
 51 (IP address leasetime)
 54 (Server identifier)
 58 (T1)
 59 (T2)
 60 (Vendor class identifier)
 66 (TFTP server name)
 67 (Bootfile name)
 128 (???)
 129 (???)
 130 (???)
 131 (???)
 132 (???)
 133 (???)
 134 (???)
 135 (???)

YIADDR: 0.0.0.0 means that the server is receiving the request but is not answering, correct? But why?

Other things I tried are changing ip=dhcp to ip=bootp and ip=:192.168.201.2::::eth0:dhcp but nothing changes.

If I set a static IP manually with:

ip=192.168.201.55:192.168.201.2:192.168.201.1:255.255.255.0:ubuntu:eth0:static

everything works, but the network is going to have many clients, I need to automate everything.

I can't figure out what I'm doing wrong.

Edit:

The DHCP server is answering:

 TIME: 2018-06-05 11:23:24.857
 IP: 192.168.201.2 (xxx) > 255.255.255.255 (ff:ff:ff:ff:ff:ff)
 OP: 2 (BOOTPREPLY)
 HTYPE: 1 (Ethernet)
 HLEN: 6
 HOPS: 0
 XID: 8d449854
 SECS: 0
 FLAGS: 7f80
CIADDR: 0.0.0.0
YIADDR: 192.168.201.11
SIADDR: 192.168.201.3
GIADDR: 0.0.0.0
CHADDR: xxx
 SNAME: .
 FNAME: gpxelinux.0.
OPTION: 53 ( 1) DHCP message type 2 (DHCPOFFER)
OPTION: 54 ( 4) Server identifier 192.168.201.2
OPTION: 51 ( 4) IP address leasetime 3164 (52m44s)
OPTION: 1 ( 4) Subnet mask 255.255.255.0
OPTION: 3 ( 4) Routers 192.168.201.1
OPTION: 6 ( 8) DNS server 208.67.222.222,8.8.8.8
OPTION: 15 ( 11) Domainname example.org
OPTION: 28 ( 4) Broadcast address 192.168.201.255

and everything looks right to me, but then why is the client not receiving this?

If someone finds this, here's how I solved it.

The bug I mentioned in my post is not actually fixed, the easiest method to fix it is to download INITRD_N11.2.2.GZ from here and put it in the folder where you have your initrd file, then add the filename in the PXE configuration after the original initrd, separated with a comma.
Also you need ip set to bootp.
So my file is now like this:

MENU LABEL Ubuntu DISKLESS
KERNEL vmlinuz-4.4.0-127-generic
APPEND boot=nfs root=/dev/nfs nfsroot=192.168.201.3:/srv/nfsroot/installer/ default,ro initrd=initrd.img-4.4.0-127-generic,INITRD_N11.2.2.GZ net.ifnames=0 biosdevname=0 ipv6.disable=1 ip=bootp

and everything works fine.

INITRD_N11.2.2.GZ is only for Ubuntu 16.04, if you have a different version check here.