Nathan Ward wrote:

On 30/06/2008, at 6:34 PM, Richard Naylor wrote:

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What worries me is that people on this list think that a network operator should be infallible. If the Internet is that important to your business, then have more than one provider. If you have clue, you'll use one with a different layer 3, 2, 1, or maybe even 0 route topology.

Yet here we are talking about potentially monopolistic metro fibre networks.

True, but we hear the same thing all over the place, everytime there is an outage. The same sort of things were said when a similar provider in another city had a similar length outage. People always seem to be caught by surprise with one provider. The fact remains... Network resilience is like Backups, UPSs, Virus checkers etc. They are hard to cost justify because if everything goes well you never need them. If things go badly, then they are too late to install. Everyone should know how much an 8 hour outage would cost their business. This way working out if you need a backup link is a simple economic issue. That or get penalty clauses written into your ISP contract. Dean

On 2008-06-30 19:49, Blair Harrison wrote:

On Mon, Jun 30, 2008 at 7:12 PM, Dean Pemberton wrote:

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True, but we hear the same thing all over the place, everytime there is an outage. The same sort of things were said when a similar provider in another city had a similar length outage. People always seem to be caught by surprise with one provider.

The fact remains... Network resilience is like Backups, UPSs, Virus checkers etc. They are hard to cost justify because if everything goes well you never need them. If things go badly, then they are too late to install.

Everyone should know how much an 8 hour outage would cost their business. This way working out if you need a backup link is a simple economic issue. That or get penalty clauses written into your ISP contract.

Dean

It seems to me (correct me if i'm wrong) that if your main provider only offers 90% uptime guarantee, your secondary provider only needs about oh.. 10% uptime guarantee... provided the downtime on the second provider doesn't occur at the same time as the first. This should be reasonably easily achieveable if you use two different access providers who don't have any shared infrastructure, preferably using a different access medium.. copper vs fibre vs wireless etc as Richard has mentioned. no use getting two telecom DSL connections and whinging when they both go down because the exchange exploded. (11kv ground anyone? :)

I think this is reasonably well available in NZ, so there's not really any excuse for not having a secondary access provider these days. Perhaps this is why nobody was talking about this here when it happened, as they just failed over, so no big deal, really.

Well, a small elephant sits quietly in the corner of the room, namely that if a customer site multi-homes, it has about three choices: a) have two IP prefixes all to itself b) NATs everything (i.e. no public IP address whatever) c) gets its own prefix advertised in BGP4 Right now there is no fourth choice and all of the above three are somewhat broken. Brian

On 2008-07-01 09:23, Dean Pemberton wrote:

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a) have two IP prefixes all to itself b) NATs everything (i.e. no public IP address whatever) c) gets its own prefix advertised in BGP4

GSLB.

Not saying it's the be-all-and-end-all of solutions, but if you're only going to keep mission critical services active during a DR (on a potentially reduced BW link) then it's not a bad solution.

I can see how it would keep your content servers accessible, but it doesn't keep your whole site on the network, does it? Also: http://www.tenereillo.com/GSLBPageOfShame.htm Brian