[j-nsp] MX104 and NetFlow - Any horror story to share?

[Olivier Benghozi]

Hi Alain,

While you seem to already be kind of suicidal (5 full tables peers on an MX104), on an MX you must not use netflow v9 (CPU based) but use inline IPFIX (Trio / PFE based).
I suppose that Netflow-v9 on an MX104 could be quickly an interesting horror story with real traffic due to its ridiculously slow CPU, by the way.
With inline IPFIX it should just take some more RAM, and FIB update could be a bit slower.

By the way on MX104 you don't configure «fpc» (bigger MXs) of «tfeb» (MX80) in chassis hierarchy, but «afeb», so you can remove your fpc line and fix your tfeb line.

So you'll need something like that in services, instead of version9:
set services flow-monitoring version-ipfix template ipv4 template-refresh-rate
set services flow-monitoring version-ipfix template ipv4 option-refresh-rate
set services flow-monitoring version-ipfix template ipv4 ipv4-template

And these ones too, to allocate some memory for the flows in the Trio and to define how it will speaks with the collector:
set chassis afeb slot 0 inline-services flex-flow-sizing
set forwarding-options sampling instance NETFLOW-SI family inet output inline-jflow source-address a.b.c.d

Of course you'll remove the line with «output flow-server <snip> source <Mgmt>».



I don't see why you quoted the mail from Brijesh Patel about the Routing licences, by the way :P


Olivier

> On 30 apr. 2018 at 21:34, Alain Hebert <ahebert at pubnix.net> wrote :
> 
> 
> Anyone has any horror stories with something similar to what we're about to do?

>     We're planning to turn up the following Netflow config (see below) on our MX104s (while we wait for our new MX960 =D), it worked well with everything else (SRX mostly), the "*s**et chassis"* are making us wonder how high would be the possibility to render those system unstable, at short and long term.
> 
>     Thanks again for your time.
> 
>     PS: We're using Elastiflow, and its working great for our needs atm.
> 
> 
> ------ A bit of context
> 
>         Model: mx104
>         Junos: 16.1R4-S1.3
> 
>     They're routing about 20Gbps atm, with 5 full tables peers, ~0.20 load average, and 700MB mem free.
> 
> 
> ------ The Netflow config
> 
> *set chassis tfeb0 slot 0 sampling-instance NETFLOW-SI*
> 
> *set chassis fpc 1 sampling-instance NETFLOW-SI*
> 
> set services flow-monitoring version9 template FM-V9 option-refresh-rate seconds 25
> set services flow-monitoring version9 template FM-V9 template-refresh-rate seconds 15
> set services flow-monitoring version9 template FM-V9 ipv4-template
> 
> set forwarding-options sampling instance NETFLOW-SI input rate 1 run-length 0
> set forwarding-options sampling instance NETFLOW-SI family inet output flow-server <snip> port 2055
> set forwarding-options sampling instance NETFLOW-SI family inet output flow-server <snip> source <Mgmt>
> set forwarding-options sampling instance NETFLOW-SI family inet output flow-server <snip> version9 template FM-V9
> set forwarding-options sampling instance NETFLOW-SI family inet output inline-jflow source-address <Mgmt>
> 
> set interfaces <X> unit <Y> family inet sampling input
> set interfaces <X> unit <Y> family inet sampling output