--- title: "Does the list of DHCP parameters need to be in hex?" slug: "aa-00334" description: "Yes." tags: ["isc dhcp"] updated: 2018-10-25T18:33:50Z published: 2018-10-25T18:33:50Z canonical: "kb.isc.org/aa-00334" stale: true --- > ## Documentation Index > Fetch the complete documentation index at: https://kb.isc.org/llms.txt > Use this file to discover all available pages before exploring further. # Does the list of parameters in the dhcp-parameter-request-list need to be in hex? Yes; if you're using the concat() syntax, the additional option numbers are represented in hex. This is because of the way that `dhcpd.conf` is parsed. As an example: 17,18 would get options 23 (default-ip-ttl) and 24 (path-mtu-aging-timeout).