RE: BGP for 2 T1's to one LAN [7:7511]

2001-06-07 Thread dragi radovanovic

hi!
go to cco and do search on bgp multihoming. you will see there are some
pretty good documents on it.
Dragi


Message Posted at:
http://www.groupstudy.com/form/read.php?f=7&i=7513&t=7511
--
FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html
Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]



Re: BGP for 2 T1's to one LAN [7:7511]

2001-06-07 Thread Rashid Lohiya

""Daniel Wilson""  wrote in message
[EMAIL PROTECTED]">news:[EMAIL PROTECTED]...
> We are trying to have the web servers in our LAN accessible to the
> internet via 2 T1's from different providers -- more for redundancy than
>
> load sharing, though that matters too.  Currently we have 2 T1's, each
> giving us a different set of IP addresses.  That just lets us put some
> sites on each T1 -- doesn't give us an ounce of redundancy.
>
> I've been told that if we get a router with 2 WIC's that can speak BGP
> (Cisco 2600 or better) that may solve our problem.  I'm very new to
> routing, so can someone answer some basic questions?
>
> Is the idea with this solution that we will be running just one set of
> IP addresses?  And that, because of BGP on our router, either ISP will
> be able to route traffic to that set of IPs on the T1 it provides?
>
> Thanks in advance.
>
> --
> Daniel Wilson, BSCS, MCP
> Application Developer
> http://www.compusoftsolutions.com/




Message Posted at:
http://www.groupstudy.com/form/read.php?f=7&i=7516&t=7511
--
FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html
Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]



RE: BGP for 2 T1's to one LAN [7:7511]

2001-06-07 Thread Vijay Ramcharan

I believe what you're looking for is a way to load balance traffic to
your web servers.  You also wish to achieve a degree of fault tolerance
in case one server goes down.  If both servers have the same content and
the content is static, you could use a feature called DNS round-robin
which basically returns a list of IP addresses to a querying client for
any single hostname.  If one server becomes unavailable the client can
use the other IP addresses given by the DNS server to access the same
site.  There's no routing protocol involved here and I don't think it's
possible to do what you need using a routing protocol.  The good thing
about DNS round-robin is that the IP addresses of the web servers could
be totally unrelated.
This seems to be more of an application specific need for fault
tolerance.  If this is possible using a routing protocol I'd be happy if
someone pointed out the error of my ways.  I'm always open to
suggestions.

Vijay Ramcharan


-Original Message-
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]] On Behalf Of
Daniel Wilson
Sent: Thursday, June 07, 2001 9:39 AM
To: [EMAIL PROTECTED]
Subject: BGP for 2 T1's to one LAN [7:7511]


We are trying to have the web servers in our LAN accessible to the
internet via 2 T1's from different providers -- more for redundancy than

load sharing, though that matters too.  Currently we have 2 T1's, each
giving us a different set of IP addresses.  That just lets us put some
sites on each T1 -- doesn't give us an ounce of redundancy.

I've been told that if we get a router with 2 WIC's that can speak BGP
(Cisco 2600 or better) that may solve our problem.  I'm very new to
routing, so can someone answer some basic questions?

Is the idea with this solution that we will be running just one set of
IP addresses?  And that, because of BGP on our router, either ISP will
be able to route traffic to that set of IPs on the T1 it provides?

Thanks in advance.

--
Daniel Wilson, BSCS, MCP
Application Developer
http://www.compusoftsolutions.com/




Message Posted at:
http://www.groupstudy.com/form/read.php?f=7&i=7520&t=7511
--
FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html
Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]



Re: BGP for 2 T1's to one LAN [7:7511]

2001-06-07 Thread Rashid Lohiya

I am reading Bassam Halabi at the moment, this has the information you
require.

Also think about who's address space you are using? ie. one of the 2 ISP's?
or your own?.
If you are using one of the ISP's address block, then maybe you will need to
NAT on the other router? This might blow your load balancing out and
complicate the issue further.
As far as I know full routing tables will not run on a 2600, you will need a
3640 with a min 128MB Memory, pls. correct me if I am wrong. So you may have
to make do with default routes.
The 2 ISP routers will run IBGP between them and EBGP back to their
Internet/ routers. They will also have OSPF running.
You may need a 3rd router running OSPF using default-originate always with
equal cost paths to both ISP routers/T1's.
I think you will need your own AS, and a /30 Serial IP address from each
ISP.


I have not implemented this myself, so pls get 2nd opinion.

Pls. correct me if I have written complete rubbish, this is the way I have
understood the setup to be.

Rashid Lohiya
[EMAIL PROTECTED]
020 8509 2990
07785 362626
www.pioneer-computers.com


""Daniel Wilson""  wrote in message
[EMAIL PROTECTED]">news:[EMAIL PROTECTED]...
> We are trying to have the web servers in our LAN accessible to the
> internet via 2 T1's from different providers -- more for redundancy than
>
> load sharing, though that matters too.  Currently we have 2 T1's, each
> giving us a different set of IP addresses.  That just lets us put some
> sites on each T1 -- doesn't give us an ounce of redundancy.
>
> I've been told that if we get a router with 2 WIC's that can speak BGP
> (Cisco 2600 or better) that may solve our problem.  I'm very new to
> routing, so can someone answer some basic questions?
>
> Is the idea with this solution that we will be running just one set of
> IP addresses?  And that, because of BGP on our router, either ISP will
> be able to route traffic to that set of IPs on the T1 it provides?
>
> Thanks in advance.
>
> --
> Daniel Wilson, BSCS, MCP
> Application Developer
> http://www.compusoftsolutions.com/




Message Posted at:
http://www.groupstudy.com/form/read.php?f=7&i=7517&t=7511
--
FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html
Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]



Re: BGP for 2 T1's to one LAN [7:7511]

2001-06-07 Thread Daniel Wilson

The quick responses on this group are great!  Thanks for the help so far.

The content is not static.  The sites in question run e-commerce.  We could
look at
setting up access from both servers to the same DB server over an internal
network ...
so that would answer that objection to the solution you offered.

I started by asking questions on a different group about round-robin DNS. 
What I was
told was that since we don't control anyone else's DNS caching settings (our
TTL entries
etc. are really only suggestions) that when one T1 goes down & we change the
DNS
settings to point to only the other line clients & other DNS servers would
still try to
access the downed T1.  Is this accurate as far as you know?  If round robin
DNS will
provide fault-tolerance, that's great.  If not ... we need to look elsewhere.

Thanks!

--
Daniel Wilson, BSCS, MCP
Application Developer
http://www.compusoftsolutions.com/

Vijay Ramcharan wrote:

> I believe what you're looking for is a way to load balance traffic to
> your web servers.  You also wish to achieve a degree of fault tolerance
> in case one server goes down.  If both servers have the same content and
> the content is static, you could use a feature called DNS round-robin
> which basically returns a list of IP addresses to a querying client for
> any single hostname.  If one server becomes unavailable the client can
> use the other IP addresses given by the DNS server to access the same
> site.  There's no routing protocol involved here and I don't think it's
> possible to do what you need using a routing protocol.  The good thing
> about DNS round-robin is that the IP addresses of the web servers could
> be totally unrelated.
> This seems to be more of an application specific need for fault
> tolerance.  If this is possible using a routing protocol I'd be happy if
> someone pointed out the error of my ways.  I'm always open to
> suggestions.
>
> Vijay Ramcharan
>
> -Original Message-
> From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]] On Behalf Of
> Daniel Wilson
> Sent: Thursday, June 07, 2001 9:39 AM
> To: [EMAIL PROTECTED]
> Subject: BGP for 2 T1's to one LAN [7:7511]
>
> We are trying to have the web servers in our LAN accessible to the
> internet via 2 T1's from different providers -- more for redundancy than
>
> load sharing, though that matters too.  Currently we have 2 T1's, each
> giving us a different set of IP addresses.  That just lets us put some
> sites on each T1 -- doesn't give us an ounce of redundancy.
>
> I've been told that if we get a router with 2 WIC's that can speak BGP
> (Cisco 2600 or better) that may solve our problem.  I'm very new to
> routing, so can someone answer some basic questions?
>
> Is the idea with this solution that we will be running just one set of
> IP addresses?  And that, because of BGP on our router, either ISP will
> be able to route traffic to that set of IPs on the T1 it provides?
>
> Thanks in advance.
>
> --
> Daniel Wilson, BSCS, MCP
> Application Developer
> http://www.compusoftsolutions.com/




Message Posted at:
http://www.groupstudy.com/form/read.php?f=7&i=7527&t=7511
--
FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html
Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]



RE: BGP for 2 T1's to one LAN [7:7511]

2001-06-07 Thread Evans, TJ

I'll take a stab at some of this ...

First - If I recall, and I may very well be wrong here, I though DNS
round-robin was solely for load-sharing, not redundancy.



Second - Regarding BGP multi-homing ... some "gotchya's" that we ran into:
You will need an ASN 
Some ISP's have netblocks designated as re-routable, if your
netblock isn't one of them they will make you re-address .
Some ISP's require a /24 netblock to be used for BGP routing
Some ISP's require that you also register your maintainer object
with RADB 
Routers must have 64mb RAM for partial/default routes  and be BGP capable 

Also, since you are doing this for fault-tolerance reasons, I would also
recommend using:
two separate routers ... 
each with 1 WIC and 2 FastEthernet interfaces
the WIC  --> ISP
Fast 0/0 --> your LAN , running HSRP 
Fast 0/1 --> other router ... this will be for iBGP 
And you could then multi-home each of your servers to each of the switches
and use NIC teaming for redundancy there



In this case - all of your outbound traffic will use the ISP connected to
the router with the "active" HSRP address, while all inbound traffic will
come in via the ISP with the lowest BGP 'cost' from the source ... not
balancing, but load sharing .



I am probably forgetting something here, but the idea is to have no single
point of failure :)
Thanks!
TJ

-Original Message-
We are trying to have the web servers in our LAN accessible to the
internet via 2 T1's from different providers -- more for redundancy than

load sharing, though that matters too.  Currently we have 2 T1's, each
giving us a different set of IP addresses.  That just lets us put some
sites on each T1 -- doesn't give us an ounce of redundancy.

I've been told that if we get a router with 2 WIC's that can speak BGP
(Cisco 2600 or better) that may solve our problem.  I'm very new to
routing, so can someone answer some basic questions?


Thanks in advance.

--
Daniel Wilson, BSCS, MCP
Application Developer
http://www.compusoftsolutions.com/

*
The information in this email is confidential and may be legally privileged.
It is intended solely for the addressee. Access to this email by anyone else
is unauthorized. 

If you are not the intended recipient, any disclosure, copying, distribution
or any action taken or omitted to be taken in reliance on it, is prohibited
and may be unlawful. When addressed to our clients any opinions or advice
contained in this email are subject to the terms and conditions expressed in
the governing KPMG client engagement letter. 
*




Message Posted at:
http://www.groupstudy.com/form/read.php?f=7&i=7528&t=7511
--
FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html
Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]



Re: BGP for 2 T1's to one LAN [7:7511]

2001-06-07 Thread Gareth Hinton

Daniel,

We've done something very similar to this by putting active/standby load
balancing devices in an ISP. Your URL then points to a VIP on the load
balancing device. The device then health checks your two sites and load
balances accordingly.
If the ISP dies then, yes you'll lose both sites, but the world is a single
point of failure.
I've not mentioned the device above, but there are various solutions
including Foundry, Cisco CSS11000 and probably a fair few more.

I believe the problem with the DNS solution is that although a DNS TTL can
be set to 0, there is only a requirement to support TTL down to 2 days. So
DNS info can be cached for this period by non-authorative DNS'.
I think there is also a problem with browsers, which can also cache DNS info
for a period of time (40 minutes rings a bell but I don't know why).
DNS seems a lovely way of doing it, and the CSS11000 seems to do it better
than some other devices I've seen, not least because it can be the
authoritive DNS itself, but I don't know if there is a way round these
caching problems.

Can any DNS guru's out there throw some ideas in?

Gaz

""Daniel Wilson""  wrote in message
[EMAIL PROTECTED]">news:[EMAIL PROTECTED]...
> The quick responses on this group are great!  Thanks for the help so far.
>
> The content is not static.  The sites in question run e-commerce.  We
could
> look at
> setting up access from both servers to the same DB server over an internal
> network ...
> so that would answer that objection to the solution you offered.
>
> I started by asking questions on a different group about round-robin DNS.
> What I was
> told was that since we don't control anyone else's DNS caching settings
(our
> TTL entries
> etc. are really only suggestions) that when one T1 goes down & we change
the
> DNS
> settings to point to only the other line clients & other DNS servers would
> still try to
> access the downed T1.  Is this accurate as far as you know?  If round
robin
> DNS will
> provide fault-tolerance, that's great.  If not ... we need to look
elsewhere.
>
> Thanks!
>
> --
> Daniel Wilson, BSCS, MCP
> Application Developer
> http://www.compusoftsolutions.com/
>
> Vijay Ramcharan wrote:
>
> > I believe what you're looking for is a way to load balance traffic to
> > your web servers.  You also wish to achieve a degree of fault tolerance
> > in case one server goes down.  If both servers have the same content and
> > the content is static, you could use a feature called DNS round-robin
> > which basically returns a list of IP addresses to a querying client for
> > any single hostname.  If one server becomes unavailable the client can
> > use the other IP addresses given by the DNS server to access the same
> > site.  There's no routing protocol involved here and I don't think it's
> > possible to do what you need using a routing protocol.  The good thing
> > about DNS round-robin is that the IP addresses of the web servers could
> > be totally unrelated.
> > This seems to be more of an application specific need for fault
> > tolerance.  If this is possible using a routing protocol I'd be happy if
> > someone pointed out the error of my ways.  I'm always open to
> > suggestions.
> >
> > Vijay Ramcharan
> >
> > -Original Message-
> > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]] On Behalf Of
> > Daniel Wilson
> > Sent: Thursday, June 07, 2001 9:39 AM
> > To: [EMAIL PROTECTED]
> > Subject: BGP for 2 T1's to one LAN [7:7511]
> >
> > We are trying to have the web servers in our LAN accessible to the
> > internet via 2 T1's from different providers -- more for redundancy than
> >
> > load sharing, though that matters too.  Currently we have 2 T1's, each
> > giving us a different set of IP addresses.  That just lets us put some
> > sites on each T1 -- doesn't give us an ounce of redundancy.
> >
> > I've been told that if we get a router with 2 WIC's that can speak BGP
> > (Cisco 2600 or better) that may solve our problem.  I'm very new to
> > routing, so can someone answer some basic questions?
> >
> > Is the idea with this solution that we will be running just one set of
> > IP addresses?  And that, because of BGP on our router, either ISP will
> > be able to route traffic to that set of IPs on the T1 it provides?
> >
> > Thanks in advance.
> >
> > --
> > Daniel Wilson, BSCS, MCP
> > Application Developer
> > http://www.compusoftsolutions.com/




Message Posted at:
http://www.groupstudy.com/form/read.php?f=7&i=7531&t=7511
--
FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html
Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]



RE: BGP for 2 T1's to one LAN [7:7511]

2001-06-07 Thread Vijay Ramcharan

Since you're running an e-commerce site then users probably establish
sessions which are dynamic in nature, passwords, logins etc.  If you
need failover capabilities you need to consider that if a failover did
occur, you'd want active, open sessions statefully failed over to the
backup server.  I'd be pretty pissed if I was in the midst of a high
dollar transaction and my session died on me.  Things could get pretty
complicated there.  The only way I know of achieving that sort of
capability is by doing clustering.  Since your application is already
installed and running, then a cluster solution is more difficult to
engineer.  Anyway this is way out of my league.  
I respectfully bow my way out of this thread to make way for someone
more versed in this arena. :-)

Vijay Ramcharan


-Original Message-
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]] On Behalf Of
Daniel Wilson
Sent: Thursday, June 07, 2001 10:42 AM
To: [EMAIL PROTECTED]
Subject: Re: BGP for 2 T1's to one LAN [7:7511]


The quick responses on this group are great!  Thanks for the help so
far.

The content is not static.  The sites in question run e-commerce.  We
could look at setting up access from both servers to the same DB server
over an internal network ... so that would answer that objection to the
solution you offered.

I started by asking questions on a different group about round-robin
DNS. 
What I was
told was that since we don't control anyone else's DNS caching settings
(our TTL entries etc. are really only suggestions) that when one T1 goes
down & we change the DNS settings to point to only the other line
clients & other DNS servers would still try to access the downed T1.  Is
this accurate as far as you know?  If round robin DNS will provide
fault-tolerance, that's great.  If not ... we need to look elsewhere.

Thanks!

--
Daniel Wilson, BSCS, MCP
Application Developer
http://www.compusoftsolutions.com/

Vijay Ramcharan wrote:

> I believe what you're looking for is a way to load balance traffic to 
> your web servers.  You also wish to achieve a degree of fault 
> tolerance in case one server goes down.  If both servers have the same

> content and the content is static, you could use a feature called DNS 
> round-robin which basically returns a list of IP addresses to a 
> querying client for any single hostname.  If one server becomes 
> unavailable the client can use the other IP addresses given by the DNS

> server to access the same site.  There's no routing protocol involved 
> here and I don't think it's possible to do what you need using a 
> routing protocol.  The good thing about DNS round-robin is that the IP

> addresses of the web servers could be totally unrelated. This seems to

> be more of an application specific need for fault tolerance.  If this 
> is possible using a routing protocol I'd be happy if someone pointed 
> out the error of my ways.  I'm always open to suggestions.
>
> Vijay Ramcharan
>
> -Original Message-
> From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]] On Behalf 
> Of Daniel Wilson
> Sent: Thursday, June 07, 2001 9:39 AM
> To: [EMAIL PROTECTED]
> Subject: BGP for 2 T1's to one LAN [7:7511]
>
> We are trying to have the web servers in our LAN accessible to the 
> internet via 2 T1's from different providers -- more for redundancy 
> than
>
> load sharing, though that matters too.  Currently we have 2 T1's, each

> giving us a different set of IP addresses.  That just lets us put some

> sites on each T1 -- doesn't give us an ounce of redundancy.
>
> I've been told that if we get a router with 2 WIC's that can speak BGP

> (Cisco 2600 or better) that may solve our problem.  I'm very new to 
> routing, so can someone answer some basic questions?
>
> Is the idea with this solution that we will be running just one set of

> IP addresses?  And that, because of BGP on our router, either ISP will

> be able to route traffic to that set of IPs on the T1 it provides?
>
> Thanks in advance.
>
> --
> Daniel Wilson, BSCS, MCP
> Application Developer
> http://www.compusoftsolutions.com/




Message Posted at:
http://www.groupstudy.com/form/read.php?f=7&i=7532&t=7511
--
FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html
Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]



RE: BGP for 2 T1's to one LAN [7:7511]

2001-06-07 Thread Bill Pearch

The answer is:  It depends.  :)
When you make use of round robin DNS your clients do recieve multiple
records.  This is from a single hit to www.microsoft.com and shows the dns
cache on the local machine.
 www.microsoft.com.
   --
 Record Name . . . . . : www.microsoft.com
 Record Type . . . . . : 5
 Time To Live  . . . . : 7124
 Data Length . . . . . : 4
 Section . . . . . . . : Answer
 CNAME Record  . . . . : 
   www.microsoft.akadns.net

 Record Name . . . . . : www.microsoft.akadns.net
 Record Type . . . . . : 1
 Time To Live  . . . . : 7124
 Data Length . . . . . : 4
 Section . . . . . . . : Answer
 A (Host) Record . . . : 
   207.46.131.91

 Record Name . . . . . : www.microsoft.akadns.net
 Record Type . . . . . : 1
 Time To Live  . . . . : 7124
 Data Length . . . . . : 4
 Section . . . . . . . : Answer
 A (Host) Record . . . : 
   207.46.230.229

 Record Name . . . . . : www.microsoft.akadns.net
 Record Type . . . . . : 1
 Time To Live  . . . . : 7124
 Data Length . . . . . : 4
 Section . . . . . . . : Answer
 A (Host) Record . . . : 
   207.46.230.218
Now, just because the host recieves this information, doesn't mean that the
host will USE all this information.  YMMV, VWPBL, TOSTCAAT.  And this only
addresses redundancy near the top of the OSI model.  You are also looking to
make redundancy happen at the bottom, and that's why you have two T-1s, and
you've gotten some good answers on that.  And if it's so bloody important,
you probably will be wanting to put in some redundancy at the server as
well, perhaps Win2K Network Load Balancing or something from the *nix world.
And remember, always ask 'What happens if Mars explodes?'
TTFN,
Bill in Anchorage

-Original Message-
If the ISP dies then, yes you'll lose both sites, but the world is a single
point of failure.
I believe the problem with the DNS solution is that although a DNS TTL can
be set to 0, there is only a requirement to support TTL down to 2 days. So
DNS info can be cached for this period by non-authorative DNS'.




Message Posted at:
http://www.groupstudy.com/form/read.php?f=7&i=7540&t=7511
--
FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html
Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]



Re: BGP for 2 T1's to one LAN [7:7511]

2001-06-07 Thread Daniel Wilson

> If the ISP dies then, yes you'll lose both sites, but the world is a single
> point of failure.

Unfortunately, all the ISP's we've worked with are much more likely to fail
than the
world is or the Internet at large is.  Both ISP's we have now (names
withheld to protect
the guilty) have bad habits of messing up their routing tables and cutting
us off.  We
will do a trace from the outside and find to routers looking at each other.
Makes for
comical traceroutes, but doesn't keep e-commerce running.

With one ISP we have to wade through support personel who think that
bringing us cell
phones will be a temporary solution before we finally (maybe) talk to
someone who knows
a router from a microwave oven.  The other ISP will tell us "we can't telnet
to your
router.  Go power-cycle it & call back."  Or they'll say, "we are connected
to your
router.  Are you sure there's a problem?"  So we are trying hard to get out
of being
dependent on any one provider.

Thank you all for all the help

--
Daniel Wilson, BSCS, MCP
Application Developer
http://www.compusoftsolutions.com/




Message Posted at:
http://www.groupstudy.com/form/read.php?f=7&i=7551&t=7511
--
FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html
Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]



RE: BGP for 2 T1's to one LAN [7:7511]

2001-06-07 Thread Symon Thurlow

-BEGIN PGP SIGNED MESSAGE-
Hash: SHA1

I am in the same position as you, we are just about to get an
additional T1, and then move the current and new T1 into a 3640.

The ISP that is managing it for us says that BGP will do the job. I
don't know much at all about BGP (although am studying now) but I
think it will work.

I am uncertain as to the best way to do it however.

I also looked at DNS round robin, and it will work, but it is a lot
uglier than using one address range and BGP. If you use DNS RR, then
when a client does a lookup, it will recieve all A records, and will
try one then the other, so there isn't that much of an issue. I don't
think it is robust enough for e-commerce sites that demand high
availability though, which is why we are going to BGP.

I will keep you updated as we go through the implementation.

Symon

- -Original Message-
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf
Of
Daniel Wilson
Sent: 07 June 2001 15:42
To: [EMAIL PROTECTED]
Subject: Re: BGP for 2 T1's to one LAN [7:7511]


The quick responses on this group are great!  Thanks for the help so
far.

The content is not static.  The sites in question run e-commerce.  We
could
look at
setting up access from both servers to the same DB server over an
internal
network ...
so that would answer that objection to the solution you offered.

I started by asking questions on a different group about round-robin
DNS. 
What I was
told was that since we don't control anyone else's DNS caching
settings (our
TTL entries
etc. are really only suggestions) that when one T1 goes down & we
change the
DNS
settings to point to only the other line clients & other DNS servers
would
still try to
access the downed T1.  Is this accurate as far as you know?  If round
robin
DNS will
provide fault-tolerance, that's great.  If not ... we need to look
elsewhere.

Thanks!

- --
Daniel Wilson, BSCS, MCP
Application Developer
http://www.compusoftsolutions.com/

Vijay Ramcharan wrote:

> I believe what you're looking for is a way to load balance traffic
> to your web servers.  You also wish to achieve a degree of fault
> tolerance in case one server goes down.  If both servers have the
> same content and the content is static, you could use a feature
> called DNS round-robin which basically returns a list of IP
> addresses to a querying client for any single hostname.  If one
> server becomes unavailable the client can use the other IP
> addresses given by the DNS server to access the same site.  There's
> no routing protocol involved here and I don't think it's possible
> to do what you need using a routing protocol.  The good thing about
> DNS round-robin is that the IP addresses of the web servers could
> be totally unrelated.
> This seems to be more of an application specific need for fault
> tolerance.  If this is possible using a routing protocol I'd be
> happy if someone pointed out the error of my ways.  I'm always open
> to
> suggestions.
>
> Vijay Ramcharan
>
> -Original Message-
> From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]] On
> Behalf Of Daniel Wilson
> Sent: Thursday, June 07, 2001 9:39 AM
> To: [EMAIL PROTECTED]
> Subject: BGP for 2 T1's to one LAN [7:7511]
>
> We are trying to have the web servers in our LAN accessible to the
> internet via 2 T1's from different providers -- more for redundancy
> than 
>
> load sharing, though that matters too.  Currently we have 2 T1's,
> each giving us a different set of IP addresses.  That just lets us
> put some sites on each T1 -- doesn't give us an ounce of
> redundancy.
>
> I've been told that if we get a router with 2 WIC's that can speak
> BGP (Cisco 2600 or better) that may solve our problem.  I'm very
> new to routing, so can someone answer some basic questions?
>
> Is the idea with this solution that we will be running just one set
> of IP addresses?  And that, because of BGP on our router, either
> ISP will be able to route traffic to that set of IPs on the T1 it
> provides? 
>
> Thanks in advance.
>
> --
> Daniel Wilson, BSCS, MCP
> Application Developer
> http://www.compusoftsolutions.com/
[EMAIL PROTECTED]

-BEGIN PGP SIGNATURE-
Version: PGPfreeware 7.0.3 for non-commercial use 

iQA/AwUBOx/pXySR4L/PyJNuEQIzlwCgn526u+eQfDo1NKjl5toGM4YgIloAniHF
rBd86dwq0wiGRUGAgXjeBQwW
=j5yI
-END PGP SIGNATURE-




Message Posted at:
http://www.groupstudy.com/form/read.php?f=7&i=7633&t=7511
--
FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html
Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]



RE: BGP for 2 T1's to one LAN [7:7511]

2001-06-07 Thread Brian Lodwick

BGP is good.
Maybe try this config?
Let's say you have have a 10.1.1.0/25 range
Send 10.1.1.0/26 out of one router with a metric of 10 and on that same 
router send 10.1.1.64/26 with a metric of 100
Then on the other router send the opposite- 10.1.1.0/26 with a metric of 100 
and 10.1.1.64/26 with a metric of 10.

>>>Brian



>From: "Symon Thurlow" 
>Reply-To: "Symon Thurlow" 
>To: [EMAIL PROTECTED]
>Subject: RE: BGP for 2 T1's to one LAN [7:7511]
>Date: Thu, 7 Jun 2001 17:07:05 -0400
>
>-BEGIN PGP SIGNED MESSAGE-
>Hash: SHA1
>
>I am in the same position as you, we are just about to get an
>additional T1, and then move the current and new T1 into a 3640.
>
>The ISP that is managing it for us says that BGP will do the job. I
>don't know much at all about BGP (although am studying now) but I
>think it will work.
>
>I am uncertain as to the best way to do it however.
>
>I also looked at DNS round robin, and it will work, but it is a lot
>uglier than using one address range and BGP. If you use DNS RR, then
>when a client does a lookup, it will recieve all A records, and will
>try one then the other, so there isn't that much of an issue. I don't
>think it is robust enough for e-commerce sites that demand high
>availability though, which is why we are going to BGP.
>
>I will keep you updated as we go through the implementation.
>
>Symon
>
>- -Original Message-----
>From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf
>Of
>Daniel Wilson
>Sent: 07 June 2001 15:42
>To: [EMAIL PROTECTED]
>Subject: Re: BGP for 2 T1's to one LAN [7:7511]
>
>
>The quick responses on this group are great!  Thanks for the help so
>far.
>
>The content is not static.  The sites in question run e-commerce.  We
>could
>look at
>setting up access from both servers to the same DB server over an
>internal
>network ...
>so that would answer that objection to the solution you offered.
>
>I started by asking questions on a different group about round-robin
>DNS.
>What I was
>told was that since we don't control anyone else's DNS caching
>settings (our
>TTL entries
>etc. are really only suggestions) that when one T1 goes down & we
>change the
>DNS
>settings to point to only the other line clients & other DNS servers
>would
>still try to
>access the downed T1.  Is this accurate as far as you know?  If round
>robin
>DNS will
>provide fault-tolerance, that's great.  If not ... we need to look
>elsewhere.
>
>Thanks!
>
>- --
>Daniel Wilson, BSCS, MCP
>Application Developer
>http://www.compusoftsolutions.com/
>
>Vijay Ramcharan wrote:
>
> > I believe what you're looking for is a way to load balance traffic
> > to your web servers.  You also wish to achieve a degree of fault
> > tolerance in case one server goes down.  If both servers have the
> > same content and the content is static, you could use a feature
> > called DNS round-robin which basically returns a list of IP
> > addresses to a querying client for any single hostname.  If one
> > server becomes unavailable the client can use the other IP
> > addresses given by the DNS server to access the same site.  There's
> > no routing protocol involved here and I don't think it's possible
> > to do what you need using a routing protocol.  The good thing about
> > DNS round-robin is that the IP addresses of the web servers could
> > be totally unrelated.
> > This seems to be more of an application specific need for fault
> > tolerance.  If this is possible using a routing protocol I'd be
> > happy if someone pointed out the error of my ways.  I'm always open
> > to
> > suggestions.
> >
> > Vijay Ramcharan
> >
> > -Original Message-
> > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]] On
> > Behalf Of Daniel Wilson
> > Sent: Thursday, June 07, 2001 9:39 AM
> > To: [EMAIL PROTECTED]
> > Subject: BGP for 2 T1's to one LAN [7:7511]
> >
> > We are trying to have the web servers in our LAN accessible to the
> > internet via 2 T1's from different providers -- more for redundancy
> > than
> >
> > load sharing, though that matters too.  Currently we have 2 T1's,
> > each giving us a different set of IP addresses.  That just lets us
> > put some sites on each T1 -- doesn't give us an ounce of
> > redundancy.
> >
> > I've been told that if we get a router with 2 WIC's that can speak
> > BGP (Cisco 2600 or better) that may solve our problem.  I'm very
> > new to routing, so can someon

Re: BGP for 2 T1's to one LAN [7:7511]

2001-06-08 Thread Sergei G.

Redundancy and loadbalancing are possible. The hardware is insufficient,
though.

Redundcy and Load balancing requirements.
--
2 ISPs
2 /24
ASN
Two routers capable of 256 Mb of DRAM (3600 and higher)
web servers with two IPs, from each block
DNS round robin

Redundancy only
--
2 ISPs
1 /24
ASN
Two routers capable of 256 Mb of DRAM (3600 and higher)

--
Sergei G""Daniel Wilson""  wrote in message
[EMAIL PROTECTED]">news:[EMAIL PROTECTED]...
> We are trying to have the web servers in our LAN accessible to the
> internet via 2 T1's from different providers -- more for redundancy than
>
> load sharing, though that matters too.  Currently we have 2 T1's, each
> giving us a different set of IP addresses.  That just lets us put some
> sites on each T1 -- doesn't give us an ounce of redundancy.
>
> I've been told that if we get a router with 2 WIC's that can speak BGP
> (Cisco 2600 or better) that may solve our problem.  I'm very new to
> routing, so can someone answer some basic questions?
>
> Is the idea with this solution that we will be running just one set of
> IP addresses?  And that, because of BGP on our router, either ISP will
> be able to route traffic to that set of IPs on the T1 it provides?
>
> Thanks in advance.
>
> --
> Daniel Wilson, BSCS, MCP
> Application Developer
> http://www.compusoftsolutions.com/




Message Posted at:
http://www.groupstudy.com/form/read.php?f=7&i=7689&t=7511
--
FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html
Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]



Re: BGP for 2 T1's to one LAN [7:7511]

2001-06-08 Thread Daniel Wilson

Thanks.  Someone else also mentioned the need for 2 routers for full
redundancy.  What
I'm not understanding is why we need to IP blocks to achieve loadbalancing. 
That we'd
need DNS round robin if we're running 2 blocks makes sense, but why the 2
blocks?  Also,
are both your lists assuming that the ISPs run BGP with us?

Thanks for the help.

--
Daniel Wilson, BSCS, MCP
Application Developer
http://www.compusoftsolutions.com/

"Sergei G." wrote:

> Redundancy and loadbalancing are possible. The hardware is insufficient,
> though.
>
> Redundcy and Load balancing requirements.
> --
> 2 ISPs
> 2 /24
> ASN
> Two routers capable of 256 Mb of DRAM (3600 and higher)
> web servers with two IPs, from each block
> DNS round robin
>
> Redundancy only
> --
> 2 ISPs
> 1 /24
> ASN
> Two routers capable of 256 Mb of DRAM (3600 and higher)
>
> --
> Sergei G""Daniel Wilson""  wrote in message
> [EMAIL PROTECTED]">news:[EMAIL PROTECTED]...
> > We are trying to have the web servers in our LAN accessible to the
> > internet via 2 T1's from different providers -- more for redundancy than
> >
> > load sharing, though that matters too.  Currently we have 2 T1's, each
> > giving us a different set of IP addresses.  That just lets us put some
> > sites on each T1 -- doesn't give us an ounce of redundancy.
> >
> > I've been told that if we get a router with 2 WIC's that can speak BGP
> > (Cisco 2600 or better) that may solve our problem.  I'm very new to
> > routing, so can someone answer some basic questions?
> >
> > Is the idea with this solution that we will be running just one set of
> > IP addresses?  And that, because of BGP on our router, either ISP will
> > be able to route traffic to that set of IPs on the T1 it provides?
> >
> > Thanks in advance.
> >
> > --
> > Daniel Wilson, BSCS, MCP
> > Application Developer
> > http://www.compusoftsolutions.com/




Message Posted at:
http://www.groupstudy.com/form/read.php?f=7&i=7706&t=7511
--
FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html
Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]



RE: BGP for 2 T1's to one LAN [7:7511]

2001-06-08 Thread Kane, Christopher A.

My opinion would be that best case calls for you to use your own netblock.
Get 2 /24's and since you are running with 2 ISPs (multi-homed) you need
your own AS. Using 2 routers on your prem and BGP with the ISPs affords you
a lot of flexibility. If you only have 1 /24 then its pretty much up to the
how the Internet sees your routes as far as which one will be used to get to
your site. With 2 /24's you can really start achieving load-sharing (not
necessarily load-balancing) Talk with the ISPs and find out what policies
they will allow you to pass to them. You could route some traffic via one
provider and the rest through the other provider. If they accept manipulated
routes (such as AS PATH PREPEND) you could then allow each ISP to back the
other one up, and they don't really need to know or care. Advertise your
whole network to both, but adjusting the routes so that half takes one ISP
while the other half takes the other ISP. Then, upon failure of one ISP, the
other would then be advertising the best/only route for your traffic. This
takes a little time to consider and hopefully knowledgeable ISP installation
techs. This also takes some consideration on your part in respect to your
host numbering and usage.

HTH

Christopher A. Kane, CCNP/CCDA
Router Ops Center/Hilliard NOC
UUNET/WCOM



-Original Message-
From: Daniel Wilson [mailto:[EMAIL PROTECTED]]
Sent: Friday, June 08, 2001 7:43 AM
To: [EMAIL PROTECTED]
Subject: Re: BGP for 2 T1's to one LAN [7:7511]


Thanks.  Someone else also mentioned the need for 2 routers for full
redundancy.  What
I'm not understanding is why we need to IP blocks to achieve loadbalancing. 
That we'd
need DNS round robin if we're running 2 blocks makes sense, but why the 2
blocks?  Also,
are both your lists assuming that the ISPs run BGP with us?

Thanks for the help.

--
Daniel Wilson, BSCS, MCP
Application Developer
http://www.compusoftsolutions.com/

"Sergei G." wrote:

> Redundancy and loadbalancing are possible. The hardware is insufficient,
> though.
>
> Redundcy and Load balancing requirements.
> --
> 2 ISPs
> 2 /24
> ASN
> Two routers capable of 256 Mb of DRAM (3600 and higher)
> web servers with two IPs, from each block
> DNS round robin
>
> Redundancy only
> --
> 2 ISPs
> 1 /24
> ASN
> Two routers capable of 256 Mb of DRAM (3600 and higher)
>
> --
> Sergei G""Daniel Wilson""  wrote in message
> [EMAIL PROTECTED]">news:[EMAIL PROTECTED]...
> > We are trying to have the web servers in our LAN accessible to the
> > internet via 2 T1's from different providers -- more for redundancy than
> >
> > load sharing, though that matters too.  Currently we have 2 T1's, each
> > giving us a different set of IP addresses.  That just lets us put some
> > sites on each T1 -- doesn't give us an ounce of redundancy.
> >
> > I've been told that if we get a router with 2 WIC's that can speak BGP
> > (Cisco 2600 or better) that may solve our problem.  I'm very new to
> > routing, so can someone answer some basic questions?
> >
> > Is the idea with this solution that we will be running just one set of
> > IP addresses?  And that, because of BGP on our router, either ISP will
> > be able to route traffic to that set of IPs on the T1 it provides?
> >
> > Thanks in advance.
> >
> > --
> > Daniel Wilson, BSCS, MCP
> > Application Developer
> > http://www.compusoftsolutions.com/




Message Posted at:
http://www.groupstudy.com/form/read.php?f=7&i=7713&t=7511
--
FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html
Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]



Re: BGP for 2 T1's to one LAN [7:7511]

2001-06-08 Thread Laszlo Csosza

Hi!

You receive one full BGP table with about 90-1 prefixes from each of the
uplink ISPs... 2 ISP, 2 full BGP table...
128MB RAM is enough...

--

cU,

Laszlo Csosza


""Sergei G.""  wrote in message
[EMAIL PROTECTED]">news:[EMAIL PROTECTED]...
> Redundancy and loadbalancing are possible. The hardware is insufficient,
> though.
>
> Redundcy and Load balancing requirements.
> --
> 2 ISPs
> 2 /24
> ASN
> Two routers capable of 256 Mb of DRAM (3600 and higher)
> web servers with two IPs, from each block
> DNS round robin
>
> Redundancy only
> --
> 2 ISPs
> 1 /24
> ASN
> Two routers capable of 256 Mb of DRAM (3600 and higher)
>
> --
> Sergei G""Daniel Wilson""  wrote in message
> [EMAIL PROTECTED]">news:[EMAIL PROTECTED]...
> > We are trying to have the web servers in our LAN accessible to the
> > internet via 2 T1's from different providers -- more for redundancy than
> >
> > load sharing, though that matters too.  Currently we have 2 T1's, each
> > giving us a different set of IP addresses.  That just lets us put some
> > sites on each T1 -- doesn't give us an ounce of redundancy.
> >
> > I've been told that if we get a router with 2 WIC's that can speak BGP
> > (Cisco 2600 or better) that may solve our problem.  I'm very new to
> > routing, so can someone answer some basic questions?
> >
> > Is the idea with this solution that we will be running just one set of
> > IP addresses?  And that, because of BGP on our router, either ISP will
> > be able to route traffic to that set of IPs on the T1 it provides?
> >
> > Thanks in advance.
> >
> > --
> > Daniel Wilson, BSCS, MCP
> > Application Developer
> > http://www.compusoftsolutions.com/




Message Posted at:
http://www.groupstudy.com/form/read.php?f=7&i=7769&t=7511
--
FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html
Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]



Re: BGP for 2 T1's to one LAN [7:7511]

2001-06-08 Thread Brian

1 /24 from each provider and round robin dns is not necessary if you get
both providers to route 1 /24.  So ithe /24 belongs tp provider a, just
talk provider b into routing it.  If you're doing bgp with them, this is a
perfectly reasonable request.

Brian "Sonic" Whalen
Success = Preparation + Opportunity


On Fri, 8 Jun 2001, Sergei G. wrote:

> Redundancy and loadbalancing are possible. The hardware is insufficient,
> though.
>
> Redundcy and Load balancing requirements.
> --
> 2 ISPs
> 2 /24
> ASN
> Two routers capable of 256 Mb of DRAM (3600 and higher)
> web servers with two IPs, from each block
> DNS round robin
>
> Redundancy only
> --
> 2 ISPs
> 1 /24
> ASN
> Two routers capable of 256 Mb of DRAM (3600 and higher)
>
> --
> Sergei G""Daniel Wilson""  wrote in message
> [EMAIL PROTECTED]">news:[EMAIL PROTECTED]...
> > We are trying to have the web servers in our LAN accessible to the
> > internet via 2 T1's from different providers -- more for redundancy than
> >
> > load sharing, though that matters too.  Currently we have 2 T1's, each
> > giving us a different set of IP addresses.  That just lets us put some
> > sites on each T1 -- doesn't give us an ounce of redundancy.
> >
> > I've been told that if we get a router with 2 WIC's that can speak BGP
> > (Cisco 2600 or better) that may solve our problem.  I'm very new to
> > routing, so can someone answer some basic questions?
> >
> > Is the idea with this solution that we will be running just one set of
> > IP addresses?  And that, because of BGP on our router, either ISP will
> > be able to route traffic to that set of IPs on the T1 it provides?
> >
> > Thanks in advance.
> >
> > --
> > Daniel Wilson, BSCS, MCP
> > Application Developer
> > http://www.compusoftsolutions.com/




Message Posted at:
http://www.groupstudy.com/form/read.php?f=7&i=7796&t=7511
--
FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html
Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]