[plug] OT: Pool of IPs for testing load-balanced connections

[Adrian Woodley]

The routing tables will only now as far as their local gateway device 
(NextG router, Satellite modem, etc), which will be performing NAT. 
Knowing that your gateway device is up doesn't necessarily imply that it 
has Internet access, especially with things like NextG and Satellite.

This is why it would be a lot easier if this style devices supported a 
better routing protocol than RIP.

Adrian

William Kenworthy wrote:
> On Fri, 2009-09-04 at 09:18 +0800, Adrian Woodley wrote:
> ...
>
> Can you side step the issue, instead of checking the "Internet", is it
> acceptable to just check that the other end of the link is up?
>
> I take it pfsense or something else requires the ping - i.e., its a
> function of the software you are using and not your own scripts?  So can
> you extract the routing table and get the address of the other end of
> the link on the fly - or alias it in the hosts file once discovered?
> ppp and other point-to-point links can give it direct from the
> interface.  It may also be possible to some kind of route discovery over
> the link to refine things (i.e., see further than just the local link,
> use the dns server given over ppp or dhcp if used - may need some simple
> logic)
>
> If you need to "know" the IP address externally (i.e., on an outside
> host looking to see when the system appears on the Internet on an
> unknown IP, use a dynamic DNS that it can update when connected.
>
> To me it seems that your routing tables will know if a link is up or
> not, so use that info.
>
> BillK
>
>
>
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