Score:0

Problems with WDS on different subnets

cn flag

I'm setting up a WDS (Windows Deployment Service), the WDS server is in a different subnet than the clients that need PXE.
These subnets are connected through a VPN tunnel. Routers are pfsense.
But on the clients' router, I don't know what settings I'm going to put for PXE to work.
I've tried going to several forums, tried several different settings and none of them seem to work.

Below are images of the current state of the network and its settings.

image1 image2 image3

in flag
WDS does more complex things than this, broadcasts and replies on UDP ort 4011 is one of them, that is hard to route, also TFTP on UDP 69 is not great over routed networks (any fragmentation kills it) WDS more or less needs to run locally, but there is lots of different PXE implementations that can run in your network, iPXE can work mostly over http instead, you just need a local TFTP server for initial boot loader file(s).
za flag
Pat
@NiKiZe, PXE works across subnetworks if you enable the corresponding IP Helpers. TFTP does not have issues with subnetworks, and routers do not fragment traffic.
in flag
@Pat, there is no guarantee that they don't, and over a wan they are not unlikely to fragment (different MTUs and it has to), so I still stand by that TFTP "is not great on routed networks"
za flag
Pat
@NiKiZe, TFTP with max packet size = 1468 => MTU=1500 => No fragmentation. TFTP is the PXE protocol used by MS WDS/MDT/SCCM and they cross router boundaries w/o problem. TFTP has issues with high latency links (i.e. Satellite links) if the latency is low and you use RFC 7440 you have no issues.
in flag
@Pat, are you claiming that MTU can never be less than 1468?, Are you also claiming that packets can't come out of order?
za flag
Pat
@NiKiZe ?? I'm not claiming those things; please reread my comment.
mangohost

Post an answer

Most people don’t grasp that asking a lot of questions unlocks learning and improves interpersonal bonding. In Alison’s studies, for example, though people could accurately recall how many questions had been asked in their conversations, they didn’t intuit the link between questions and liking. Across four studies, in which participants were engaged in conversations themselves or read transcripts of others’ conversations, people tended not to realize that question asking would influence—or had influenced—the level of amity between the conversationalists.