[f-nsp] MLX throughput issues

[Jethro R Binks]

On Fri, 13 Feb 2015, Brad Fleming wrote:

> Over the years we’ve seen odd issues where one of the 
> switch-fabric-links will “wigout” and some of the data moving between 
> cards will get corrupted. When this happens we power cycle each switch 
> fab one at a time using this process:
>
> 1) Shutdown SFM #3
> 2) Wait 1 minute
> 3) Power SFM #3 on again
> 4) Verify all SFM links are up to SFM#3
> 5) Wait 1 minute
> 6) Perform steps 1-5 for SFM #2
> 7) Perform steps 1-5 for SFM #3
>
> Not sure you’re seeing the same issue that we see but the “SFM Dance” 
> (as we call it) is a once-every-four-months thing somewhere across our 
> 16 XMR4000 boxes. It can be done with little to no impact if you are 
> patient verify status before moving to the next SFM.

That's all interesting.  What code versions is this?  Also, how do you 
shutdown the SFMs?  I don't recall seeing documentation for that.

Jethro.


> 
> > On Feb 13, 2015, at 11:41 AM, nethub at gmail.com wrote:
> > 
> > We have three switch fabrics installed, all are under 1% utilized.
> >  
> >  
> > From: Jeroen Wunnink | Hibernia Networks [mailto:jeroen.wunnink at atrato.com <mailto:jeroen.wunnink at atrato.com>] 
> > Sent: Friday, February 13, 2015 12:27 PM
> > To: nethub at gmail.com <mailto:nethub at gmail.com>; 'Jeroen Wunnink | Hibernia Networks'
> > Subject: Re: [f-nsp] MLX throughput issues
> >  
> > How many switchfabrics do you have in that MLX and how high is the utilization on them
> > 
> > On 13/02/15 18:12, nethub at gmail.com <mailto:nethub at gmail.com> wrote:
> >> We also tested with a spare Quanta LB4M we have and are seeing about the same speeds as we are seeing with the FLS648 (around 20MB/s or 160Mbps).
> >>  
> >> I also reduced the number of routes we are accepting down to about 189K and that did not make a difference.
> >>  
> >>  
> >> From: foundry-nsp [mailto:foundry-nsp-bounces at puck.nether.net <mailto:foundry-nsp-bounces at puck.nether.net>] On Behalf Of Jeroen Wunnink | Hibernia Networks
> >> Sent: Friday, February 13, 2015 3:35 AM
> >> To: foundry-nsp at puck.nether.net <mailto:foundry-nsp at puck.nether.net>
> >> Subject: Re: [f-nsp] MLX throughput issues
> >>  
> >> The FLS switches do something weird with packets. I've noticed they somehow interfere with changing the MSS window size dynamically, resulting in destinations further away having very poor speed results compared to destinations close by. 
> >> 
> >> We got rid of those a while ago.
> >> 
> >> 
> >> On 12/02/15 17:37, nethub at gmail.com <mailto:nethub at gmail.com> wrote:
> >>> We are having a strange issue on our MLX running code 5.6.00c.  We are encountering some throughput issues that seem to be randomly impacting specific networks.
> >>>  
> >>> We use the MLX to handle both external BGP and internal VLAN routing.  Each FLS648 is used for Layer 2 VLANs only.
> >>>  
> >>> From a server connected by 1 Gbps uplink to a Foundry FLS648 switch, which is then connected to the MLX on a 10 Gbps port, running a speed test to an external network is getting 20MB/s.
> >>>  
> >>> Connecting the same server directly to the MLX is getting 70MB/s.
> >>>  
> >>> Connecting the same server to one of my customer's Juniper EX3200 (which BGP peers with the MLX) also gets 70MB/s.
> >>>  
> >>> Testing to another external network, all three scenarios get 110MB/s.
> >>>  
> >>> The path to both test network locations goes through the same IP transit provider.
> >>>  
> >>> We are running NI-MLX-MR with 2GB RAM, NI-MLX-10Gx4 connect to the Foundry FLS648 by XFP-10G-LR, NI-MLX-1Gx20-GC was used for directly connecting the server.  A separate NI-MLX-10Gx4 connects to our upstream BGP providers.  Customer’s Juniper EX3200 connects to the same NI-MLX-10Gx4 as the FLS648.  We take default routes plus full tables from three providers by BGP, but filter out most of the routes.
> >>>  
> >>> The fiber and optics on everything look fine.  CPU usage is less than 10% on the MLX and all line cards and CPU usage at 1% on the FLS648.  ARP table on the MLX is about 12K, and BGP table is about 308K routes.
> >>>  
> >>> Any assistance would be appreciated.  I suspect there is a setting that we’re missing on the MLX that is causing this issue.
> >>> 
> >>> 
> >>> 
> >>> 
> >>> _______________________________________________
> >>> foundry-nsp mailing list
> >>> foundry-nsp at puck.nether.net <mailto:foundry-nsp at puck.nether.net>
> >>> http://puck.nether.net/mailman/listinfo/foundry-nsp <http://puck.nether.net/mailman/listinfo/foundry-nsp>
> >> 
> >> 
> >> 
> >> -- 
> >>  
> >> Jeroen Wunnink
> >> IP NOC Manager - Hibernia Networks
> >> Main numbers (Ext: 1011): USA +1.908.516.4200 | UK +44.1704.322.300 
> >> Netherlands +31.208.200.622 | 24/7 IP NOC Phone: +31.20.82.00.623
> >> jeroen.wunnink at hibernianetworks.com <mailto:jeroen.wunnink at hibernianetworks.com>
> >> www.hibernianetworks.com <http://www.hibernianetworks.com/>
> > 
> > 
> > -- 
> >  
> > Jeroen Wunnink
> > IP NOC Manager - Hibernia Networks
> > Main numbers (Ext: 1011): USA +1.908.516.4200 | UK +44.1704.322.300 
> > Netherlands +31.208.200.622 | 24/7 IP NOC Phone: +31.20.82.00.623
> > jeroen.wunnink at hibernianetworks.com <mailto:jeroen.wunnink at hibernianetworks.com>
> > www.hibernianetworks.com <http://www.hibernianetworks.com/>_______________________________________________
> > foundry-nsp mailing list
> > foundry-nsp at puck.nether.net <mailto:foundry-nsp at puck.nether.net>
> > http://puck.nether.net/mailman/listinfo/foundry-nsp <http://puck.nether.net/mailman/listinfo/foundry-nsp>
> 

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Jethro R Binks, Network Manager,
Information Services Directorate, University Of Strathclyde, Glasgow, UK

The University of Strathclyde is a charitable body, registered in
Scotland, number SC015263.