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jwil1
18-08-2010, 11:23 PM
Hi all,

At work we have just implemented a new VLAN setup but have discovered a couple of problems. One of which is that we can't PXE boot off the network when the PXE server is on a different VLAN to the client. It works fine if they are on the same VLAN.

:help:

nedkelly
18-08-2010, 11:33 PM
(My response is from thinking you have a router with sub-interfaces setup)
There should be some way on the router to allow that kind of traffic to traverse the vlans.
(Wow 10:30 at night and I used a big word right, I think)

Erayd
19-08-2010, 01:33 AM
Hi all,

At work we have just implemented a new VLAN setup but have discovered a couple of problems. One of which is that we can't PXE boot off the network when the PXE server is on a different VLAN to the client. It works fine if they are on the same VLAN.

:help:VLANS are designed to logically split a single switched network into several completely isolated networks at layer 2. If the PXE server is on a different VLAN, then as far as the client is concerned it might as well not exist.

If you want to make PXE available on other VLANs, then you will need to configure your router to pass BOOTP/DHCP/TFTP traffic across VLANs to / from the PXE server, as Nedkelly notes above.

Alternatively, you can set the PXE server up for layer 2 multihoming - although this isn't really a good idea, as it adds another potential security hole and needlessly complicates your network topology. Getting the router to manage this is a better solution.

Note that unless a particular resource is visible via the router, your clients will not be able to access that resource unless it's connected to the same VLAN. This applies to *every* piece of equipment connected to your network. It's also worth pointing out the obvious here - all traffic to / from VLANs other than the one the client is connected to will need to go via the router, so unless you're not doing much inter-VLAN communication your router could easily become a major bottleneck.

SolMiester
19-08-2010, 09:29 AM
Hi all,

At work we have just implemented a new VLAN setup but have discovered a couple of problems. One of which is that we can't PXE boot off the network when the PXE server is on a different VLAN to the client. It works fine if they are on the same VLAN.

:help:

VLAN for Virtual hosts?.....will yes that is correct, a virtual LAN means a separate network from the host network, device are not supposed to talk across VLANs!

nedkelly
19-08-2010, 09:50 AM
But a router can be set up to allow them to, sol

SolMiester
19-08-2010, 09:52 AM
But a router can be set up to allow them to, sol

Yes, I didnt say you cant!.....is the OP talking a switch or router

Erayd
19-08-2010, 03:15 PM
Yes, I didnt say you cant!.....is the OP talking a switch or router

VLANs implies that there is at least one switch involved, and any setup that expects stuff to talk across VLANs should have a router. If the OP doesn't have both I'd be very surprised.

:pf1mobmini: