Juniper SRX DHCP Server for Windows Deployment Services

In my network, a Juniper SRX cluster handles all DHCP leases (via an IP helper configured on the switches with DHCP snooping). These are the steps I used to get the DHCP server for SRX devices to work for Windows Deployment Services.

Main DHCP Configuration

The following configuration is set for the DHCP pool:

access {
    address-assignment {
        pool VL100 {
            family inet {
                network 192.168.30.0/24;
                range VL100 {
                    low 192.168.30.5;
                    high 192.168.30.229;
                }
                dhcp-attributes {
                    maximum-lease-time 86400;
                    grace-period 345600;
                    domain-name internal.dreamscapenetworks.com;
                    name-server {
                        10.254.1.10;
                        10.254.1.11;
                    }
                    router {
                        192.168.30.254;
                    }
                    boot-file "boot\x64\wdsnbp.com";
                    boot-server 192.168.90.23;
                    tftp-server 192.168.90.23;
                    option 42 array ip-address [ 10.1.254.10 10.1.254.11 ];
                }
            }
        }
    }
}

The important parts that must be defined for this to work are boot-server and tftp-server; the IP for those options should be the IP of the Windows Deployment Services server. If you do not define the tftp-server option the TFTP client will try downloading the file from the SRX device.

Setting the boot file

One issue I encountered when setting the boot-file option is the SRX CLI was parsing the back slashes as a hex character, so after setting the boot-file option it looked like this:

boot-file "bootd\wdsnbp.com";

To get around this, first convert the value to hex. As an example, to set the boot-file to boot\x64\wdsnbp.com:

set access address-assignment pool VL100 family inet dhcp-attributes boot-file "\x62\x6f\x6f\x74\x5c\x78\x36\x34\x5c\x77\x64\x73\x6e\x62\x70\x2e\x63\x6f\x6d"

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