
Cumulus Linux – first impressions - liotier
http://packetlife.net/blog/2014/oct/1/cumulus-linux-first-impressions/
======
hhw
If everything is more or less stock Linux, what value does Cumulus actually
add for it to be worth the licensing costs?

This all seems to be a giant step backwards. JunOS is now the gold standard
for its CLI and configuration, due to being highly structured and well
organised. Being able to validate configurations before committing them, and
automatic rollbacks with commit confirm is a much improved way of doing things
over IOS. Given that Juniper hardware can often be bought significantly
discounted, the cost savings of white box gear are going to be small, if at
all. Thus far, they seem to be sold in such small volumes that comparable
Juniper or Cisco gear can easily be purchased for less.

Also, how exactly is Cumulus separating the control plane and data plane? From
the look of things, SDN is going to end up being relegated to just easy
automation instead, like how Cloud has just been relegated to VMs with
flexible billing instead of abstracting underlying infrastructure.

~~~
wmf
In theory, the value of Cumulus is (1) support and (2) their proprietary
switchd. (Edit: I also second the other comments that Cumulus licensing
appears to be _really_ cheap. But if you're looking for "CentSwitch" you're
out of luck.)

 _Also, how exactly is Cumulus separating the control plane and data plane?_

They're not. Cumulus is kind of anti-SDN.

~~~
drdaeman
"Proprietary" means "if you ever have issues with that that our support won't
be able to solve for you in meaningful time span, you're basically out of
luck".

We're running a gateway router on Vyatta/VyOS and with every single hardware
and software change we had some issues. Most were relatively minor (like
default settings being not appropriate for our workload), already
documented/solved by someone on the 'net. Some had required reading source
code and debugging/profiling to see what goes on. Must also admit, some were
beyond my understanding and were mysteriously solved with some shamanism and
voodoo magic (like randomly tinkering with firmware and driver version
combos).

------
dmix
The use of Linux and commodity hardware is interesting but when I read some of
the sales copy on the Cumulus website I was reminded of why I hate enterprise
software.

> The emerging software-defined data center (SDDC) paradigm involves automated
> control of all network, server, storage and application resources, resulting
> in a cloud operating system. Unified visibility is essential, enabling the
> cloud operating system to efficiently allocate resources, detect problems
> and ensure consistent performance.

~~~
jeffmcjunkin
My interpretation: "You can manage your network hardware in Ansible and Git.
We'll assume that everything else is using it, too."

Still pretty attractive, and a lot less Buzzword Bingo.

~~~
StavrosK
Oh man, I just had flashbacks of pages and pages of enterprise lingo that were
much less clear than your sentence. I think Ansible suffered from that at one
point, too.

------
Someone1234
I think it is very safe to say that most dedicated "smart" network hardware is
going to disappear in the next 5-15 years to be replaced by virtual machines
acting as several pieces of network equipment.

You just patch in all the cables straight onto effectively a Hypervisor, and
then you generate virtual switches, routers, firewalls, and so on completely
via the VM management console.

You're already seeing some of Cisco's smaller competition go this way. It
saves physical space, works on standard hardware, and is easier to centrally
manage (as you aren't physically moving wires after initial install).

It will be interesting to see if Cisco jumps aboard this train or continues to
pretend like the sands underneath it aren't shifting. I'm sure there would be
a market for VMs running Cisco's IOS, it is still by far the most popular
network operating system.

~~~
m-app
"I think it is very safe to say that most dedicated "smart" network hardware
is going to disappear in the next 5-15 years to be replaced by virtual
machines acting as several pieces of network equipment."

I agree with this idea in that most of the intelligence will be pushed out
towards the edges of the network and overlay networks will make a lot of the
physical network invisible to the applications and even the management.
However, this does not mean that the networking hardware can all be just dumb
devices. First of all, this kind of imperative networking will not scale to
large data center implementations and secondly dumb devices will become
useless once disconnected from their controller.

"It will be interesting to see if Cisco jumps aboard this train or continues
to pretend like the sands underneath it aren't shifting. I'm sure there would
be a market for VMs running Cisco's IOS, it is still by far the most popular
network operating system."

The way Cisco is getting into the SDN market is by leveraging Application
Centric Infrastructure (ACI) to define the complete DC (Compute, Storage and
Network) with templates and letting the whole system configure itself. The
switches supporting this infrastructure are based on merchant silicon in
combination with Cisco ASIC's to provide the most optimal performance at these
intelligent edges. Add to that the available open API's and the investment in
OpenStack and you have a rock-solid and cost-effective solution for the future
of the DC and DevOps.

Cisco ACI: [http://cisco.com/go/aci](http://cisco.com/go/aci)

I would love to talk about it more if you want. These are exciting times. Hit
me up on email or IRC.

(Disclaimer: I work for Cisco but these thought are still my own, yada yada)

------
voidlogic
>These appear as Ethernet interfaces normally do on Linux, visible with ip
link show. (ifconfig has long been deprecated by the community in favor of the
iproute2 family of tools.)

I am amused when I read things like this, 99% of the Linux savvy folks I know
use ifconfig.

~~~
LukeShu
In my experience: we use ifconfig out of familiarity; I know that I "should"
be using 'ip' (and I do for scripts).

~~~
a3176082
I don't think you should. Every UNIX operating system has ifconfig. Writing a
nonstandard tool instead of fixing the standard one is very antisocial
behaviour from the Linux community, mirroring that of Microsoft. Have a look
for example at how excellent the ifconfig program for OpenBSD is. These days
Linux has become so popular, that it starts to pretend other operating systems
and standards are no longer relevant.

------
liotier
TL;DR : Linux all the way, ready for large-scale provisioning automation.

------
Thaxll
What is the performance, does it bypass the kernel for the network stack or
it's just a linux bundled with compatible hardware?

~~~
wmf
Forwarding is done in hardware so it's line rate. Those swp interfaces aren't
real interfaces; they're just proxies.

------
pyvpx
but is it faster than VALE/netgraph?

~~~
wmf
Yes, hardware forwarding is ~100x faster than optimized software forwarding.

~~~
pyvpx
I missed the switchd/proprietary ASIC part. oops!

