We are building a new Spectrum system with the following:
Site 1: 12.000 routers / switches, 12.000 Pingables
Site 2: 8.000 routers / switches 19.000 Pingables
The Spectrum Sizer Tool recommends:
with WATCHes the sizer calculates 4 servers
without WATCHes the sizer calcukates 2 servers
All supported DX NetOps Spectrum releases
It is difficult to give a recommendation based on just the number of devices as there are many other factors that influence the resources needed.
With the introduction of 64bit Spectrum, the limit per SS is 1 million models (not devices). We document model count and not device count and some devices create many, many more models than others e.g. large switches with a huge interface count. With the introduction of huge landscapes can go as high as 2 million but for these numbers the resources on the server will need to be much especially RAM than what is documented. If all your switches have thousands of interfaces, you will go over the 2 million model count.
Landscapes and the Distributed SpectroSERVER
The number of models is not as important as the traffic they generate which is what costs the SS and OC servers. e.g. 1 server that is creating traps storms can have a bigger cost to the resources than 1000, that are not.
Also How often are the watches run? This was not considered by the sizer.
The recommendation for device numbers based on other clients would be:
2,000 devices conservative, 3000 aggressive but I would not recommend any more than that. Again it depends on the device type, pingables are not going to matter much
unless they are sending traps to Spectrum. With the routers and switches, again it depends on the number of models each one creates and how much traffic they generate but to allow room for growth, you should aim conservatively.
Some customers limit to 1,000 devices per landscape. Others will use a lot more and up the resources (mostly RAM).
The current sizer tool is slightly outdated and a new NetOps sizer tool is currently being developed which takes many more factors into account.