real hardware router VS linux router

mike mike-nanog at
Thu Feb 19 15:05:46 UTC 2009


    Our operation uses linux everywhere and we have our own in house 
tiny embedded flavor with all the tools and things that make it suited 
for use in big and small boxes as many kinds of router and general 
packet flipping appliance. I have confidence built on long term, real 
world experience that says I can do this sucessfully, but the price I 
pay for it is the knowledge curve and having had to invent the 'right' 
mix of stuff, which includes compact flash based boot media, read-only 
filesystem, and minimal management (command line via ssh, you need to be 
an expert), and as well as having had to select the right hardware 
(constraints include power on always, no dumb bios to stop the boot 
process, and other issues).

    I would never ever reccomend that anyone just 'use linux' for 
network appliances. It *can* do the job, but all the baggage of 'pc 
hardware' typically conspires to make for less than rock solid. Stuff 
like hard disks, which crash malfunction corrupt, and issues like - does 
the box power on when power is applied or does someone have to press a 
button? (You will note, most commercial hardware like routers and 
switches either don't have a power button, or simply default to being 
'on' unless you take pains to flip buttons somewhere. But, PC's 
typically have a power button you have to press to make it come on). And 
there's other issues too - PC Bios's also conspire to get in the way and 
stop the boot process. If they detect some sort of error, a key press, a 
missing disk, or many other excuses, they stop cold waiting for someone 
to 'press f1 to continue', or worse. Also most PC systems also have 
single power supply units, and that which are less sturdy construction 
and are more likely to burn out at some point than the more heavy duty 
commercial grade units you see in commercial router/switch equipment).

    The difference then between linux and 'a hardware router' then is 
that the manufacturer - cisco, juniper, whomever - has a large degree of 
control over the integration between their software and the hardware it 
runs on, and can dictate all of the things that makes the product work 
like the boot process and it's internal storage and wether there are 
sufficient fans and what kind of power supplie(s) are present and wether 
there's a hardware watchdog (that works!) and the type of chips serving 
as the ethernet controllers (which dictates all kinds of things that the 
mnf considers 'features'). It's a long list.

    To summarize, you can do many jobs with linux. How WELL you do them, 
however, is more of a function of how much exerience and knowledge that 
you have. You can also do many jobs with commercial boxes, but how well 
you do that job can be expressed more in terms of selecting the right 
platform and plugging the right configuration lines into it, and both of 
these can easilly be 'done well' in exchange for money (router vendor 
support team, etc).


Deric Kwok wrote:
> Hi All
> Actually, what is the different hardware router VS linux router?
> Have you had experience to compare real router eg: cisco VS linux router?
> eg: streaming speed... tcp / udp
> Thank you for your information

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