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Stevo
01-Jul-2014, 15:31
Anyone ever set up a dhcp pool with multiple default
gateway/router/whatever addresses?

Does it work where if the first address is not available, the second
one becomes the default gateway?

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Stevo

Simon Flood
01-Jul-2014, 15:52
On 01/07/2014 15:31, Stevo wrote:

> Anyone ever set up a dhcp pool with multiple default
> gateway/router/whatever addresses?
>
> Does it work where if the first address is not available, the second
> one becomes the default gateway?

The default gateway is just that, the default gateway. You can't have
more than one.

What you could do is assign a gateway to one pool of addresses and a
second gateway to another pool so hedging your bets.

HTH.
--
Simon
Novell Knowledge Partner

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Simon Flood
01-Jul-2014, 15:54
On 01/07/2014 15:52, Simon Flood wrote:

> What you could do is assign a gateway to one pool of addresses and a
> second gateway to another pool so hedging your bets.

Or approach it from a different angle and set up fault tolerance at
network level. For instance with Cisco routers you can use HSRP or VRRP
to configure a virtual router address which is shared by two physical
routers and you hand out the virtual router address to clients.

HTH.
--
Simon
Novell Knowledge Partner

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Stevo
01-Jul-2014, 16:09
Simon Flood sounds like they 'said':

> The default gateway is just that, the default gateway. You can't have
> more than one.
>
> What you could do is assign a gateway to one pool of addresses and a
> second gateway to another pool so hedging your bets.

So my response to Simon's comment is...

Not quite sure how this could be done here. Here's my setup.

Had a site that was on a T-1, doing dhcp from our main location with
another location as the redundant backup dhcp location.

Now, the T-1 is gone, and the remote site connects via pt to pt
wireless with the redundant backup dhcp location.

I want to keep the remote site (that was via T-1) to have their normal
default gateway, which is local to their building.

Kicker is, a few people there use thin clients to connect to VMs that
are currently housed at our main location. We'd like to have these VMs
reside at the backup location so they would be in the same address
range, etc as the physical machines.

Technically, the VMs would have a different gateway (at the backup dhcp
location) than the physical machines (at the old T-1 location). I have
the remote site's default gateway as the local switch, while the VMs'
default gateway is the switch at the backup dhcp location.

Clear as mud now? ;-) See my predicament?

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Stevo

Stevo
01-Jul-2014, 16:16
Ok, changed my thinking a bit.

I set everyone there to have a default gateway of the switch at the
backup dhcp location.

I figure if for whatever reason if the pt to pt wireless is down, it
won't matter what the default gateway is, they won't get a dhcp address
anyway, as that site will be down.

duuuhhhh.......... :-)


--
Stevo