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BGP Enabled transit in Chicago (River North) and equipment recommendation

They are obviously not running full tables on their 3640. I'd imagine a 
raspberry pi would have more BGP capability and throughput than a 3640, 
though I don't recommend doing that even as a joke. But an ERR would be 
fine if they're expecting nothing more than a slightly faster 3640 with 
maybe some extra features.

On 9/3/19 3:54 PM, Florian Brandstetter via NANOG wrote:
> Ubiquiti's EdgeRouter Lite is equipped with 512 MiB of DDR2 memory, of 
> which after startup, roughly 491 MiB can be utilized. 119 MiB of the 
> remaining memory are allocated by the base of the router already, 
> which leaves you with a remainder of 372 MiB memory. Memory usage 
> depends on the architecture for objects, for example there's a large 
> difference between x86 and x86_64, since on x86_64, the compiler will 
> generally use 64bit boundaries to be faster; the ERL runs on a MIPS64 
> architecture, which will have a similar trade-off. To get to the 
> point, let's have a quick look at the components using memory: bgpd, 
> zebra, kernel. Roughly 180 MiB of memory are required to keep a single 
> full table in bgpd alone, leaving you with 192 MiB of free memory. 
> Accounting further, zebra will eat at least another 100 MiB for 
> exporting the BGP RIB to the Kernel (FIB), leaving you with 100 MiB. 
> At this point, you have a mere 92 MiB left for fitting the routes into 
> the kernel, and to leave room for RX buffers on sockets.
> I don't see full tables happening from a memory perspective on the 
> EdgeRouter Lite, you would want to look at something with at least 2 
> GiB of memory to keep the whole system running smoothly, and when 
> using Quagga and Zebra, that's still aimed rather low. FRRouting at 
> this point uses 2 GiB for 4 full tables on an x86 system, without any 
> magic attached.
> Having kept it unmentioned, the EdgeRouter Lite has a dual-core with 
> 500 MHz, and surely your BGP updates processing isn't offloaded, hence 
> you will pretty quickly kill the whole router when you flood it with a 
> full table, unless you set very low queue sizes, which isn't really 
> reliable though since you generally want BGP to converge fast - not 
> after a period of 15 minutes with the CPU sitting on 100%.
> You might want to install something like OpenWRT (which I don't know 
> the possibility of on an ERL), and run BIRD if you're tied to a low 
> memory footprint, however, in a base vendor-generic setup of the ERL, 
> it's beyond my understanding why one would even suggest running a full 
> table on it.
> Sent from Mailspring 
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