Re: nLayer IP transit

2013-08-02 Thread Richard A Steenbergen
On Fri, Aug 02, 2013 at 07:11:34AM +1000, Mark Tees wrote:
 Thanks for the replies.
 
 I think I saw somewhere around the Cloudflare outage post someone 
 mentioning that since the person at Juniper that was responsible for 
 Flowspec left it all went down hill.
 
 I take it then Flowspec is still used internally then? I am still 
 wondering if its best to avoid Flowspec and roll your own firewall 
 rules applied via Netconf for transit interfaces to achieve the same 
 sort of functionality.

It's a lot less likely to go south if you control the routes that go 
into the system. That said, it still breaks some things just by having 
it enabled (like NSR, though I suppose one could argue that NSR breaks 
itself :P), so you might be better served with a netconf distribution of 
rules if you want to avoid those potential issues.

-- 
Richard A Steenbergen r...@e-gerbil.net   http://www.e-gerbil.net/ras
GPG Key ID: 0xF8B12CBC (7535 7F59 8204 ED1F CC1C 53AF 4C41 5ECA F8B1 2CBC)



Re: nLayer IP transit

2013-08-01 Thread Saku Ytti
On (2013-08-01 10:00 +1000), Mark Tees wrote:

 I remember reading a while back that customers of nLayer IP transit
 services could send in Flowspec rules to nLayer. Anyone know if that is
 true/current?

Anyone planning to do this might want to be aware that the validation
process of flowspec does not limit actions.

In practice this means, if you do run flowspec to your customers, your
customers likely can inject traffic to arbitrary VRFs.

I feel RFC should have explicitly stated valid actions for validation
process, which operator MAY change, and any other action MUST cause
validation process to fail.


-- 
  ++ytti



Re: nLayer IP transit

2013-08-01 Thread Alexandre Snarskii
On Thu, Aug 01, 2013 at 09:13:59AM +0300, Saku Ytti wrote:
 On (2013-08-01 10:00 +1000), Mark Tees wrote:
 
  I remember reading a while back that customers of nLayer IP transit
  services could send in Flowspec rules to nLayer. Anyone know if that is
  true/current?
 
 Anyone planning to do this might want to be aware that the validation
 process of flowspec does not limit actions.

 In practice this means, if you do run flowspec to your customers, your
 customers likely can inject traffic to arbitrary VRFs.

You can match flow actions by extended communities and not accept
actions you do not like. For example, to permit only discard action
you can match 

community flow_discard members traffic-rate:*:0;

Or am I missing something ? 

 I feel RFC should have explicitly stated valid actions for validation
 process, which operator MAY change, and any other action MUST cause
 validation process to fail.
 
 
 -- 
   ++ytti

-- 
In theory, there is no difference between theory and practice. 
But, in practice, there is. 




Re: nLayer IP transit

2013-08-01 Thread Saku Ytti
On (2013-08-01 11:35 +0400), Alexandre Snarskii wrote:

 You can match flow actions by extended communities and not accept
 actions you do not like. For example, to permit only discard action
 you can match 
 
 community flow_discard members traffic-rate:*:0;
 
 Or am I missing something ? 

No you're not missing anything. This is what I implied with 'likely', I
feel validation check should guarantee eBGP safety as most operators won't
deploy additional security via manual config, because issue isn't mentioned
in RFC or vendor docs.

-- 
  ++ytti



Re: nLayer IP transit

2013-08-01 Thread Richard A Steenbergen
On Thu, Aug 01, 2013 at 10:00:49AM +1000, Mark Tees wrote:
 Howdy listers,
 
 I remember reading a while back that customers of nLayer IP transit 
 services could send in Flowspec rules to nLayer. Anyone know if that 
 is true/current?

We were forced to stop offering flowspec connections to customers, after 
we started experiencing a rash of issues with it. Among other things, we 
found ways for flowspec generated rules to easily cause non line-rate 
performance on Juniper MX boxes, and we had a couple of incidents where 
customer generated routes were able to cause cascading failure behaviors 
like crashing the firewall compiler processes across the entire network.

I previously mentioned some of this here:

http://mailman.nanog.org/pipermail/nanog/2011-January/030051.html

There have also been a few other high profile outages caused by bugs in 
the Juniper implementation, for example:

https://support.cloudflare.com/entries/23294588-CloudFlare-Post-Mortem-from-Outage-on-March-3-2013

As a concept I still very much like Flowspec, and wish we could continue 
to offer it to customers, but as with any new routing protocol there 
are significant risks of network-wide impact if the implementation is 
not stable.

IMHO Juniper has done a horrible job of maintaining support for Flowspec 
in recent years, and has effectively abandoned doing the proper testing 
and support necessary to run it in production. Until that changes, or 
until some other major router vendors pick it up and do better with it, 
I don't expect to see any major changes in this position any time soon.

-- 
Richard A Steenbergen r...@e-gerbil.net   http://www.e-gerbil.net/ras
GPG Key ID: 0xF8B12CBC (7535 7F59 8204 ED1F CC1C 53AF 4C41 5ECA F8B1 2CBC)



Re: nLayer IP transit

2013-08-01 Thread Mark Tees
Thanks for the replies.

I think I saw somewhere around the Cloudflare outage post someone mentioning 
that since the person at Juniper that was responsible for Flowspec left it all 
went down hill.

I take it then Flowspec is still used internally then? I am still wondering if 
its best to avoid Flowspec and roll your own firewall rules applied via Netconf 
for transit interfaces to achieve the same sort of functionality.

On 02/08/2013, at 3:30 AM, Richard A Steenbergen r...@e-gerbil.net wrote:

 On Thu, Aug 01, 2013 at 10:00:49AM +1000, Mark Tees wrote:
 Howdy listers,
 
 I remember reading a while back that customers of nLayer IP transit 
 services could send in Flowspec rules to nLayer. Anyone know if that 
 is true/current?
 
 We were forced to stop offering flowspec connections to customers, after 
 we started experiencing a rash of issues with it. Among other things, we 
 found ways for flowspec generated rules to easily cause non line-rate 
 performance on Juniper MX boxes, and we had a couple of incidents where 
 customer generated routes were able to cause cascading failure behaviors 
 like crashing the firewall compiler processes across the entire network.
 
 I previously mentioned some of this here:
 
 http://mailman.nanog.org/pipermail/nanog/2011-January/030051.html
 
 There have also been a few other high profile outages caused by bugs in 
 the Juniper implementation, for example:
 
 https://support.cloudflare.com/entries/23294588-CloudFlare-Post-Mortem-from-Outage-on-March-3-2013
 
 As a concept I still very much like Flowspec, and wish we could continue 
 to offer it to customers, but as with any new routing protocol there 
 are significant risks of network-wide impact if the implementation is 
 not stable.
 
 IMHO Juniper has done a horrible job of maintaining support for Flowspec 
 in recent years, and has effectively abandoned doing the proper testing 
 and support necessary to run it in production. Until that changes, or 
 until some other major router vendors pick it up and do better with it, 
 I don't expect to see any major changes in this position any time soon.
 
 -- 
 Richard A Steenbergen r...@e-gerbil.net   http://www.e-gerbil.net/ras
 GPG Key ID: 0xF8B12CBC (7535 7F59 8204 ED1F CC1C 53AF 4C41 5ECA F8B1 2CBC)



nLayer IP transit

2013-07-31 Thread Mark Tees
Howdy listers,

I remember reading a while back that customers of nLayer IP transit
services could send in Flowspec rules to nLayer. Anyone know if that is
true/current?

Thanks,

-- 
Regards,

Mark


Re: nLayer IP transit

2013-07-31 Thread Patrick W. Gilmore
On Jul 31, 2013, at 20:00 , Mark Tees markt...@gmail.com wrote:

 I remember reading a while back that customers of nLayer IP transit
 services could send in Flowspec rules to nLayer. Anyone know if that is
 true/current?

Not any more.

-- 
TTFN,
patrick



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