Good morning all,
I have a nice easy one for someone out there i'm sure......
I have been asked to bridge and existing LAN to another site office at the other end of the country:
LAN <> WAN <LAN>
Currently the existing LAN has no external connectivity and everything is on the same subnet, servers and users.
I have no NETFLOW or network management or monitoring software as this LAN started off very small and grew over time and was thrown together by those using it and not anyone working in the network field.
All i have is the stats from the two main ESX servers hosting the VMs at the existing site showing throughput in KBps (attached).
I need to be able to calculate what the WAN bandwidth requirements are based on this information, I have had a go (shown below) but I am not sure if I am working this out correctly and I have no one I can ask in my company to verify this for me.
My working out
Server ending .100 shows avg throughput of 10,000KBps (10MBps)
10MB (10,000KB) * 8 = 80,000Kbps (8Mbps)
So on average this server uses 8Mbps throughout the day peaking at 40MB or 32Mbps in the early hours (which I suspect to be a backup)
Server 2 ending .101 is the same working out which = avg 16Mbps
8Mbps + 16Mbps + overhead of roughly 30% (8Mbps) = 32Mbps bandwidth required on the WAN link for this service
This shows us the total bandwidth required for these servers, but most of this is going to be local to the main site i.e. from Main Site Existing LAN to the Server resources hosted locally at that site.
We are looking at a small number of users in the Remote site transiting the WAN to access these server resources (exact number to be confirmed but I expect this to be around 10 as a maximum at least initially)
Therefore we could take the not overly scientific approach as divide 32Mbps of bandwidth currently being utilized by the servers and devide this by the current number of users using these central servers (understood to be around 300) and then multiply by 10 to get the total bandwidth required over the WAN.
For example, 32Mbps /300 = 0.1 Mbps per user * 10 (users) = 1Mbps bandwidth required
Given an average medium usage office worker’s IT bandwidth consumption is roughly calculated to be 80Kbps by industry guidelines I guess this is a plausible figure.
Does this sound about right, I really need some help and your guidance is greatly appreciated?
Thanks in advance,