Load Balancing 3 DSL Connections

Soldato
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Greetings, im looking to bond three ADSL Max connections into a single circuit, this would be achieved using Cisco Equipment, now i know that Cisco don't natively support true bonding as bonding is an awful but do have three methods of load balancing namely GLBP, HSRP and VRRP.

My intial idea was to configure three Cisco 877's in a single GLBP group in load balancing mode or use a single 2801 with three ADSL WIC's installed, static routers and similar metrics.

Has anyone attempted the above before and had relatively good success?
 
Never done that exact setup myself but GLBP would be the way forward, as HSRP and VRRP would only allow an active-standby setup as I understand it.
//TrX
 
Never done that exact setup myself but GLBP would be the way forward, as HSRP and VRRP would only allow an active-standby setup as I understand it.
//TrX


Indeed the other option i was considering was an Xrio Q-Balancer but i realy am not a fan to be honest.
 
If you have cisco's, I would go with them... at least try it out on a test setup (or would you have to buy the WIC's ?)
Even then, cisco kit usually does what they say they will. Maybe have a gander on the cisco website and read the GLBP docs, just to make sure you are not going to run into any stumbling blocks.

Other than that I really don't have enough experience of GLBP to comment further.

EDIT: you could also do this with linux, But guess you ruled that out as it sounds like you are doing an enterprise class install (guessed this from you mentioning cisco's from the offset)

//TrX
 
You've got to question if your customer can afford a 2801 and 3x WICs then maybe they can afford a proper internet connection?

You're talking £2000+ list price, more like £1200 at real prices but still. Having a cisco won't help when BT's dslam has a fit...

It'll work with GLBP but it doesn't change the fact it's a silly setup.
 
This is true, but I tend to find if someone is implementing an ADSL setup, then they have already had to settle due to costs/location etc.

Plus, A Cisco is a one-off expense, which is nothing compared to the ongoing cost's of decent SLA decent bandwidth net connections.

//TrX
 
Greetings, im looking to bond three ADSL Max connections into a single circuit, this would be achieved using Cisco Equipment, now i know that Cisco don't natively support true bonding as bonding is an awful but do have three methods of load balancing namely GLBP, HSRP and VRRP.

My intial idea was to configure three Cisco 877's in a single GLBP group in load balancing mode or use a single 2801 with three ADSL WIC's installed, static routers and similar metrics.

Has anyone attempted the above before and had relatively good success?

Are these xDSL circuits for the purpose of connecting a remote site in a WAN P2P fashion? or do you wish to bond 3 xDSL connections for internet use?

If its to connect like a WAN, configure 3 GRE tunnels back to the endpoint (HO?) and run EIGRP or OSPF over each GRE tunnel, the remote site then learns each route with an identical metric, each route appears in the table with 3 best paths, it also advertises its conneced LAN range back across the 3 tunnels where the HO does exactly the same. Be careful with tunnels, because the rule of split horizon is easily broken and the remote site can re-advertise networks it learnt from the HO back out of the other tunnel interfaces, (EIGRP Stub connected, is your friend) <we do this all the time>
Just make sure, if its IPVPN/MPLS, that the ISP isn't injecting your LAN range via BGP on the xDSL gateways, as that will break it, the LAN ranges should all be learnt across the tunnels.

If you want to do this with 3 internet connections, its impossible to get 3x the bandwidth for each session without the use of BGP, as the internet needs to know that there are 3 ways back to you.
 
I assumed (bad thing to do) that you were talking about internet access, not P2P trunking (in which case, yes, GRE+OSPF is the way forward)

Also V-Spec is right, 3 links will not give you a 'Fat Pipe' for one big download (unless your ISP offers bgp on all of your links) but will load balance TCP sessions across the gateways for if you had to many users for your current 1 gateway's bandwidth.. (Should really have mentioned that also for completeness, but you seemed to know exactly what you were talking about ;) )

//TrX
 
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You've got to question if your customer can afford a 2801 and 3x WICs then maybe they can afford a proper internet connection?

You're talking £2000+ list price, more like £1200 at real prices but still. Having a cisco won't help when BT's dslam has a fit...

It'll work with GLBP but it doesn't change the fact it's a silly setup.

Not necessarily as a partner of both Comstor and Cisco we receive very attractive discounts and 70% reduced on NFR equipment.

Are these xDSL circuits for the purpose of connecting a remote site in a WAN P2P fashion? or do you wish to bond 3 xDSL connections for internet use?

If its to connect like a WAN, configure 3 GRE tunnels back to the endpoint (HO?) and run EIGRP or OSPF over each GRE tunnel, the remote site then learns each route with an identical metric, each route appears in the table with 3 best paths, it also advertises its conneced LAN range back across the 3 tunnels where the HO does exactly the same. Be careful with tunnels, because the rule of split horizon is easily broken and the remote site can re-advertise networks it learnt from the HO back out of the other tunnel interfaces, (EIGRP Stub connected, is your friend) <we do this all the time>
Just make sure, if its IPVPN/MPLS, that the ISP isn't injecting your LAN range via BGP on the xDSL gateways, as that will break it, the LAN ranges should all be learnt across the tunnels.

If you want to do this with 3 internet connections, its impossible to get 3x the bandwidth for each session without the use of BGP, as the internet needs to know that there are 3 ways back to you.

Unfortunately not as the site in question is a standalone entity ive done similar configs but using Policy Based Routing with EIGRP on point to point serial links. Nice that you remembered my queries with MPLS but this is a different project :)

I would very much like to configure this in a lab environment but its difficult to simulate DSL circuits. The customer has insisted that make the full bandwidth available to all users ive tried to explain that the load can be shared between links but they are a little stubborn and dont understand the underlying implications.

I good friend of mine is the technical lead for a company out of Nottingham who specialises in DSL Services using the Xrio equipment, only difference in this case is that they have equipment in all exchanges as well as at the CP so that links are terminated end to end.

Cheers for the replies guys, good information as usual
 
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Of course the other option if you have a friendly ISP is to put a 1841 or similar at the datacenter end and run 3 tunnels to that using OSPF and then route out from there...obviously you'll need a friendly ISP (unless you have some rack space already).

Obviously it's another messy solution which I wouldn't do for a customer myself but I can confirm it works because I do it at home.
 
Of course the other option if you have a friendly ISP is to put a 1841 or similar at the datacenter end and run 3 tunnels to that using OSPF and then route out from there...obviously you'll need a friendly ISP (unless you have some rack space already).

Obviously it's another messy solution which I wouldn't do for a customer myself but I can confirm it works because I do it at home.

Your ISP let you install a 1841 in your ISP's local POP? May I ask which ISP you are with / where?

Cheers,
//TrX
 
Your ISP let you install a 1841 in your ISP's local POP? May I ask which ISP you are with / where?

Cheers,
//TrX

I'm a infrastructure architect for an ISP, I have a 2821 in my lab at work I terminate the tunnels on (which has a pure gigabit path to our edge routers). 2x ADSL Max and a 1841 at home and I don't pay a penny for it.

The benefits of working in the industry I suppose but I also work from home a lot and it's actually really useful for testing purposes.

As a solution I've looked at doing it for customers but I'm wonderfully keen on it, in the end it's not in our interest as it we can sell faster links instead and our target market isn't afraid of spending money.
 
That's a fair point, but for your own purposes that rocks.
Nice job BTW,
What path did you take into it if you don't mind me asking?

*If this is de-railing the thread please feel free to PM me instead of replying here*

//TrX
 
That's a fair point, but for your own purposes that rocks.
Nice job BTW,
What path did you take into it if you don't mind me asking?

*If this is de-railing the thread please feel free to PM me instead of replying here*

//TrX

The sneaky path if I'm honest, we have some very big customers but operate with a fairly small team so there's been good opportunities for promotion within the company.

I started doing senior NOC work, then moved to fill an infrastructure engineer role and then convinced my boss we needed DNS servers and such as well as network infrastructure (and I share core network design work with a dedicated network architect).

Qualifications wise I'm waiting for cisco to confirm the CCDE practical exam so I can start prepping for that and I have a lot of juniper qualifications as we use the M series as our core routers. RHCE as well as I do a lot of Linux. Overall I'm slightly under-qualified and very young for the job but I'm holding my own.
 
Pretty young too, but consider myself able to meet the demands of a job like that,
Net security is what I eventually want to end up in, but network design + implementation also interests me (with big setups such as yours, bored of medium size company networks TBH with small budgets and management refusing to spend money on much needed infrastructure :P)

If your company grows and need some extra hands i'd be up for an interview :P My last job was sneakily slipped into, seems like all the best ones are :)

Good luck anyways!
//TrX
 
Pretty young too, but consider myself able to meet the demands of a job like that,
Net security is what I eventually want to end up in, but network design + implementation also interests me (with big setups such as yours, bored of medium size company networks TBH with small budgets and management refusing to spend money on much needed infrastructure :P)

If your company grows and need some extra hands i'd be up for an interview :P My last job was sneakily slipped into, seems like all the best ones are :)

Good luck anyways!
//TrX

The technical bit is rapidly becoming the easiest bit of the job for me, the 60 hour weeks and stresses of being responsible for it all are my headache (especially when you're as forgetful as me!).

My current headache is a flagship project which is delayed because the people who do such things won't assign a postcode to the new building and until they do our dark fibre provider refuses to acknowledge it exists and can't provision the links... I'd much more happily deal with BGP issues...
 
Maybe not on such a large scale... But I know the feeling..

Mmm, Dark fiber.... I have a postcode.. feel free to run some to me if you want ;).. preferably with a backbone connection at the other end :)

//TrX
 
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