Dual ADSL lines
Discussion
We are fairly dependant on ADSL for our businessbut we have always used residential ADSL lines. I spent a while recently looking at Business lines but they are very expensive and no more reliable (on the grounds that contention isn't a measure of reliability).
We have a number of physical lines into the building so what are the possibilities about running 2 Adsl lines to one router? i konw it can be done but how reliable is it? if we turned all our lines into IP lines would our double lines create an issue?
does anyone have any real world experience of doing this?
We have a number of physical lines into the building so what are the possibilities about running 2 Adsl lines to one router? i konw it can be done but how reliable is it? if we turned all our lines into IP lines would our double lines create an issue?
does anyone have any real world experience of doing this?
Your issue isn't the router - there are loads of devices that will support ADSL fail-over to ADSL, ISDN or basic dial-up. Your problem is going to be that most ADSL failures happen at the exchange and both your lines are almost certainly going to be coming from the same exchange.
You would be better with getting an ADSL line with fail-over to say cable (NTL/Telewest) if available in your area.
Alternatively, what about a leased line with SLA and maybe fail-over to something else? This is relatively expensive but not ridiculous if it's a low specification leased line.
Finally, do you have a good 3G signal where you business is located? If so, you could fail-over to 3G as a last resort by equipping your server with a datacard and having connection sharing, or you could give individual cards out to key machines/personnel?
Hope some of the above is helpful!
roadie.
You would be better with getting an ADSL line with fail-over to say cable (NTL/Telewest) if available in your area.
Alternatively, what about a leased line with SLA and maybe fail-over to something else? This is relatively expensive but not ridiculous if it's a low specification leased line.
Finally, do you have a good 3G signal where you business is located? If so, you could fail-over to 3G as a last resort by equipping your server with a datacard and having connection sharing, or you could give individual cards out to key machines/personnel?
Hope some of the above is helpful!
roadie.
roadsweeper said:
Your problem is going to be that most ADSL failures happen at the exchange and both your lines are almost certainly going to be coming from the same exchange.
Once they've got out of your building the lines will be likely to take exactly the same route back to the exchange too, so aren't safe from "2@ with JCB" either.
agent006 said:
roadsweeper said:
Your problem is going to be that most ADSL failures happen at the exchange and both your lines are almost certainly going to be coming from the same exchange.
Once they've got out of your building the lines will be likely to take exactly the same route back to the exchange too, so aren't safe from "2@ with JCB" either.
I've seen a server farm with multiple redundancies built in taken out by 2@ with JCB. I think the JCB is like the deathstar... doesn't matter what you do... it just wins.
arfur said:
SDSL is your friend ... Go look into it
Unless you want to stick with ADSL and it's being used for webhosting, then use DYNDNS to host the DNS and roundrobin through two routers and ip addresses ... Should work well
Unless you want to stick with ADSL and it's being used for webhosting, then use DYNDNS to host the DNS and roundrobin through two routers and ip addresses ... Should work well
No its not, you still get the same physical line problems as you do with ADSL, add the fact that its even more rate-adaptive, and thus next to no-one can bloody get a decent line (plus its contended as well).
The only way, as suggested, to do it cheaply is to have a 3G router on standby - you can buy devices now that take a 3G card, and failover when the ADSL goes down.
Not cheap if the ADSL stays down (3G is per Mb charged usually) however, it will be the cheapest upfront installation cost, compared to ADSL with an SLA.
Other than that, you could go the route of ADSL, with a bonded ISDN backup - but that can be pricey.
Ultimatly, ISPs know that this sort of of thing is really important, and as such, charge appropriately
Edited by Neil_Bolton on Tuesday 9th January 09:52
I don't really work at this end of the market, but.....
I can see how you can use one ADSL line to back the other up - pointless though as has already been said, as you are going to the same exchange, sharing the same path etc...
But surely if you load balance / aggregate there must be issues with this ?
You essentially have two point to point IP links, both with different IP addresses etc, can you have assymetric routing issues etc ? Pretty clever if you can make it work....
If I were hosting, and it actually mattered, I'd put in a leased line service of some kind (LES ?) and maybe use ADSL etc as a backup. If it really mattered, and generated significant income I'd put it in a dedicated datacentre where they specialise in hosting, have redundant links etc and rely on their SLAs.
The JCB will still get you in the end - it gets EVERYONE, but at least they have to pay up if it does....
I can see how you can use one ADSL line to back the other up - pointless though as has already been said, as you are going to the same exchange, sharing the same path etc...
But surely if you load balance / aggregate there must be issues with this ?
You essentially have two point to point IP links, both with different IP addresses etc, can you have assymetric routing issues etc ? Pretty clever if you can make it work....
If I were hosting, and it actually mattered, I'd put in a leased line service of some kind (LES ?) and maybe use ADSL etc as a backup. If it really mattered, and generated significant income I'd put it in a dedicated datacentre where they specialise in hosting, have redundant links etc and rely on their SLAs.
The JCB will still get you in the end - it gets EVERYONE, but at least they have to pay up if it does....
- if it REALLY mattered, then the client will pay. Neil_Bolton said:
arfur said:
SDSL is your friend ... Go look into it
Unless you want to stick with ADSL and it's being used for webhosting, then use DYNDNS to host the DNS and roundrobin through two routers and ip addresses ... Should work well
Unless you want to stick with ADSL and it's being used for webhosting, then use DYNDNS to host the DNS and roundrobin through two routers and ip addresses ... Should work well
No its not, you still get the same physical line problems as you do with ADSL, add the fact that its even more rate-adaptive, and thus next to no-one can bloody get a decent line (plus its contended as well).
The only way, as suggested, to do it cheaply is to have a 3G router on standby - you can buy devices now that take a 3G card, and failover when the ADSL goes down.
Not cheap if the ADSL stays down (3G is per Mb charged usually) however, it will be the cheapest upfront installation cost, compared to ADSL with an SLA.
Other than that, you could go the route of ADSL, with a bonded ISDN backup - but that can be pricey.
Ultimatly, ISPs know that this sort of of thing is really important, and as such, charge appropriately
Edited by Neil_Bolton on Tuesday 9th January 09:52
My SDSL lines are 1:1 contention with 4 hr SLA ... work perfectly for website and VPN access
As to the backup, that's two different ADSL providers ( both with their own kit in the exchange ) and simply DNS roundrobin to keep the performance up to sratch. Admittedly there is no roundrobin for the VPN but if there is a problem, then the website is more important anyhow
arfur said:
Neil_Bolton said:
arfur said:
SDSL is your friend ... Go look into it
Unless you want to stick with ADSL and it's being used for webhosting, then use DYNDNS to host the DNS and roundrobin through two routers and ip addresses ... Should work well
Unless you want to stick with ADSL and it's being used for webhosting, then use DYNDNS to host the DNS and roundrobin through two routers and ip addresses ... Should work well
No its not, you still get the same physical line problems as you do with ADSL, add the fact that its even more rate-adaptive, and thus next to no-one can bloody get a decent line (plus its contended as well).
The only way, as suggested, to do it cheaply is to have a 3G router on standby - you can buy devices now that take a 3G card, and failover when the ADSL goes down.
Not cheap if the ADSL stays down (3G is per Mb charged usually) however, it will be the cheapest upfront installation cost, compared to ADSL with an SLA.
Other than that, you could go the route of ADSL, with a bonded ISDN backup - but that can be pricey.
Ultimatly, ISPs know that this sort of of thing is really important, and as such, charge appropriately
Edited by Neil_Bolton on Tuesday 9th January 09:52
My SDSL lines are 1:1 contention with 4 hr SLA ... work perfectly for website and VPN access
As to the backup, that's two different ADSL providers ( both with their own kit in the exchange ) and simply DNS roundrobin to keep the performance up to sratch. Admittedly there is no roundrobin for the VPN but if there is a problem, then the website is more important anyhow
Thats fine.
However, pricey I'd wager (can you tell us how much?)
In this instance, I don't think the OP is really looking to fork out £3k+ (i'm guessing here based upon experience)* for this sort of service.
Additionally, bear in mind that SDSL is not available everywhere, and also may only be available due to LLU.
However, if it's cheap, gimme their telephone number
* IIRC £4k was the figure touted for a Gold service SLA on a bogo ADSL line...however this may be cheaper/more expensive depending on which way the wind is blowing.
Edited by Neil_Bolton on Tuesday 9th January 15:51
ThePassenger said:
agent006 said:
roadsweeper said:
Your problem is going to be that most ADSL failures happen at the exchange and both your lines are almost certainly going to be coming from the same exchange.
Once they've got out of your building the lines will be likely to take exactly the same route back to the exchange too, so aren't safe from "2@ with JCB" either.
I've seen a server farm with multiple redundancies built in taken out by 2@ with JCB. I think the JCB is like the deathstar... doesn't matter what you do... it just wins.
), you have no idea how true this really is!! Neil_Bolton said:
guydw said:
The JCB will still get you in the end - it gets EVERYONE, but at least they have to pay up if it does....
Not if you use 3G Routers
We had this happen to one of our clients last year when i was an outsourcing whore. Digger took out a load of fibres including both the supposedly diversely routed connections for a call centre we were running. A bit of bodging had them back online using the GPRS card in my laptop... for a week (bloody BT).
guydw said:
OH yes Neil 3G too - last year an entire MPLS network, carrying 3G traffic, was taken out by a JCB in one place and a stray bullet (honestly) hiting fibre on the underside of a motorway bridge at the same time.
But that is what SLAs are for...
But that is what SLAs are for...
I'd like to not believe it, but being a IT type, I just imagine the shaken heads of the poor saps on call who had to attend to and explain that one...Gassing Station | Computers, Gadgets & Stuff | Top of Page | What's New | My Stuff