Member Avatar for ben.matthews18

Hi,

I've recently got my first tech guy job and i've nearly got my head around how all the servers and stuff works in the IT department. I have thought of something though.

when you PXE boot a client into WDS and install an image onto the client machine and then boot the pc up how does the client pick up an automatic DNS address without having to go into the adapter properties and manually adding it?

Thanks

  • 3 Contributors
  • 4 Replies
  • 203 Views
  • 1 Month Discussion Span
  • Latest Post Latest Post by hazzag1995

Dani AI

Generated

Short answer: the DNS server address is pushed to the NIC by DHCP (the DHCP scope option that lists DNS servers is option 006). PXE is just the boot-time use of DHCP to get an IP/boot info; once the installed OS starts it requests DHCP again and receives the same DHCP-provided DNS servers. (learn.microsoft.com)

A few practical points tied to the replies from and : if a home router has DHCP enabled it will answer clients faster than the server and its DNS settings will be used. Common fixes are to disable the router’s DHCP and let the Windows DHCP service own the subnet, or place the clients and server on the same switch/VLAN. If clients and the WDS/DHCP server live on different subnets, use the router’s IP-helper (DHCP relay) to forward requests rather than trying to “force” PXE using DHCP boot options. (learn.microsoft.com)

If WDS and the DHCP role are on the same machine, don’t let both bind to UDP 67: configure WDS to not listen on the DHCP/BOOTP ports and enable the DHCP option that signals PXE (option 60 = "PXEClient") on the DHCP server. If DHCP is on another server or you cross VLANs, use IP-helper or configure per-scope options only when IP-helper isn’t available. Example commands to add option 60 on a Windows DHCP server: 

netsh dhcp server \\DHCPServerName add optiondef 60 PXEClient STRING 0
netsh dhcp server \\DHCPServerName set optionvalue 60 STRING PXEClient

See Microsoft’s guidance for these settings and PXE troubleshooting. (learn.microsoft.com)

Quick troubleshooting checklist: on the client run ipconfig /all and ipconfig /renew to confirm the DNS server list; on the DHCP server check Scope/Server Options for option 006 (DNS Servers); enable WDS debug logging if needed and inspect the WDS debug folder; and make sure DNS dynamic update/aging is configured so A/PTR records are registered and stale records scavenged. (learn.microsoft.com)

References: DHCP scopes documentation (DHCP Scopes), PXE/DHCP interaction guidance (PXE clients don't start / IP helper note), PXE troubleshooting and WDS/DHCP options (Advanced PXE troubleshooting, wdsutil /Set-Server), and Dynamic DNS update behavior (Dynamic update).

Recommended Answers

All 4 Replies

Member Avatar for JorgeM

The IP configuration is coming from your DHCP servers.

PxE depends on DHCP.

Edited by JorgeM
Member Avatar for ben.matthews18

Thanks, i've installed the DHCP role on the server and added a scope. I'm also behind a home router that gives out automatic ip addresses. Could that be an issue? Should i just connect the computers to a switch and see if that makes a difference?

Member Avatar for JorgeM

You will need to disable the DHCP role on the router. Also, with regard to WDS, you may need additional options configured in the scope depending on which server(s) have which role (WDS and DHCP). There are plenty of TechNet articles on how to set this up.

Member Avatar for hazzag1995

Maybe only use the router to provide your server with an internet connection, and have your DHCP/DNS/WDS server instead of the router, aslong as clients are connected to the server rather than through the router it will work. if they connect through the router, they take the routers configuration, vice versa with the servers. In case you aren't using it, may i recommend using the microsoft Deployment Toolkit, found at http://www.microsoft.com/en-us/download/details.aspx?id=25175

You can use this to customize many settings, including domain, and network settings to a certain extent. Good luck and happy new year!

Be a part of the DaniWeb community

We're a friendly, industry-focused community of developers, IT pros, digital marketers, and technology enthusiasts meeting, networking, learning, and sharing knowledge.