SRX Services Gateway
SRX Services Gateway

Cannot get PXE boot working with DHCP on SRX

‎07-14-2014 03:16 PM

I have problems getting PXE boot to work.

My configuration:

[edit access address-assignment pool Lokaal family inet dhcp-attributes]
onno@router# show
maximum-lease-time 14400;
next-server 10.0.2.250;
name-server {
    10.0.2.1;
    208.67.220.220;
    208.67.220.222;
}
router {
    10.0.2.1;
}
boot-file pxelinux.0;
boot-server 10.0.2.250;

 

The problem (I think) is the fact that the router is not sending the next-server address. The client connects to the router itself because the next-server field is empty.

Bootp flags: 0x8000 (Broadcast)
Client IP address: 0.0.0.0 (0.0.0.0)
Your (client) IP address: 10.0.2.120 (10.0.2.120)
Next server IP address: 0.0.0.0 (0.0.0.0)
Relay agent IP address: 0.0.0.0 (0.0.0.0)
Client MAC address: WistronI_36:80:08 (20:6a:8a:36:80:08)
Client hardware address padding: 00000000000000000000
Server host name: 10.0.2.250
Boot file name: pxelinux.0
Magic cookie: DHCP
<snip>
Option: (66) TFTP Server Name
TFTP Server Name: 10.0.2.250
Option: (67) Bootfile name
Bootfile name: pxelinux.0

 

Why is it not sending the next-router address? Is this a bug,one that's present for serveral versions?

I'm running JUNOS Software Release [12.1X46-D20.5] on Model: srx210he2.

JNCIA-Junos, JNCIS-SEC, CCNA, LPI1, soon more...
4 REPLIES 4
SRX Services Gateway

Re: Cannot get PXE boot working with DHCP on SRX

‎07-18-2014 07:26 AM

Am I the only one with this problem?

JNCIA-Junos, JNCIS-SEC, CCNA, LPI1, soon more...
SRX Services Gateway

Re: Cannot get PXE boot working with DHCP on SRX

‎07-23-2014 02:17 AM

Hi OnnoO,

 

To be honest, I haven't tried yet but did you want to try to configure the next-server (and the rest of the related configuration) parameters under the [edit system services dhcp pool Lokaal] instead?

 

Cheers,

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SRX Services Gateway

Re: Cannot get PXE boot working with DHCP on SRX

‎07-23-2014 12:53 PM

When I configure DHCP under system services it works fine, but then I lose my DHCPv6-PD functionality.

JNCIA-Junos, JNCIS-SEC, CCNA, LPI1, soon more...
SRX Services Gateway

Re: Cannot get PXE boot working with DHCP on SRX

[ Edited ]
‎07-27-2017 05:44 PM

I had the exact same issue. jdhcpd sets next server in DHCP Offer packet to 0.0.0.0 even though next-server is configured. I was able to fix it because this PXE client had another way to determine the boot server IP, which may or may not work for you:

option 43 hex-string 06010f08070000xxxxxxxx01ff;
option 60 string PXEClient;

 

Where xxxxxxxx is the hex-encoded version of the IP address. This corresponds to the following PXE options:

 

PXE_DISCOVERY_CONTROL : DISABLE_BCAST_DISCOVER | DISABLE_MCAST_DISCOVER | ENABLE_USE_SERVER_LIST | DISABLE_PROMPT_MENU
06 01 0f

PXE_BOOT_SERVERS : type = 0, IPs = [ a.b.c.d ]
08 07 00 00 xx xx xx xx 01

PXE_END
ff

Edit: this is not sufficient for some clients. Another thing you can try is overriding the server address:

option 54 ip-address a.b.c.d;