[DannyJ7]

Hello,

I do not have a lot of networking experience, but I need to research networking solutions for a large project.

The situation is as follows: A large employee database (let's say 50,000 employees) already exists and is fully functional. If I want to create an online system for employees to access their payroll records, I need to have a general idea of what hardware and software is required.

From my basic understanding, I assume that the new system would not run on the same system as the existing database, right? It would be necessary to deploy new hardware to run the employee interface and to retrieve data from the database as per employee requests, correct? I assume a web server would be necessary for this. I think something like a C# program utilizing ASP.NET would be appropriate for handling employee login and retrieving database info via SQL.

What is confusing me most is the hardware requirement. Let's say that these 50,000 employees are logging into the system from different geographic locations, that's quite a lot of users. What type of server would be able to handle this volume of requests? I'm a bit lost here, so could someone please clue me in as to what might be a viable hardware solution?

Sorry if I sound dumb!

Thanks!

[Septerra]

Well if your users are in different geographical locations then, it might be best to set up a few web server and perform load balancing between all of them.

I say several webservers is because if all 50,000 users would attempt to connect to one web server, there is potential chance of literally crashing the application to access your SQL database, not to mention it would be a Denial of Service attack on your web server.

[DannyJ7]

Thank you for your informative reply. I did wonder about this. I am unsure of how many users a single web server can typically handle at one time. If I use several servers, would the application be running on each one, or would the application just be running on the "main" server with the other servers acting to control traffic?

Also, can you recommend a specific server brand/model which would be appropriate for this application? I did some online research and found all kinds of servers in different shapes and sizes, and I looked at Dell, Cisco, and IBM. I just have no idea which kind of servers would be required in this case. I guess that kind of knowledge just comes with experience. Can you point me in the right direction?

Thanks!

[Septerra]

well, all the web servers would be running the same application and then you would have a load balancer that sits in front of them that will distribute the load accordingly across all your web servers.

Typically, if there was 50,000, you should look at blade servers as they can support multiple cpu's with multi-core's to handle all the data access and SQL connections.

I am also making the assumption that the Payroll system has replication of some sort cause I don't know if SQL can handle all 50,000 concurrent connections to it. If that's not the case then you should set up multiple SQL with the same database and put them into a cluster.

[DannyJ7]

Any particular blade server? So let's say I run 3 blade servers, then they would all be running the same application and they would all be running some type of server software (IIS, Apache) right? Then I would use a single hardware load-balancer connected to the three blade servers.

I appreciate your comment about about replication. I am allowed to make some assumptions in this case, so I will assume the payroll system does have replication, to avoid making things more complicated. Can you just explain a little more what replication actually means in this case?

Also, is there anything else I have overlooked here in terms of hardware? I need to address security somehow, but I can make the assumption that the existing system already has a perimeter firewall. Is it necessary to add additional routing, packet-filtering, or screening with this sub-system, or can I just make use of the existing network's infrastructure?

Thank you so much!

[DannyJ7]

How do I know how many servers I really need? Is there a rule for determining how many are required?

[Septerra]

To me its any blade server is based on preference and the kind of hardware support you wish to have. I don't have a particular brand, although we run mostly Dell Blade Servers here. As for hardware specs, that is something you will need to determine based on the theoretical load.

You are correct on that part with running 3 webservers all on the same platform, running the same app and have them connected to a load balancer.

Replication for SQL in general means to replicate data between other SQL server's to provide redundancy and a higher up time. Also this prevents small to massive outages that could impact business continuity.

In your case, this would mean that if you had replication set up (i.e. 4 SQL database), then if one SQL database ever went down then you would still have 3 more to rely up for continuity and uptime, where as if you had one SQL and it went down, you would be in a mad dash attempting to rebuild the server without data lost while have 50,000 screaming at you to get it up and running because it is a crucial part of the business.

This is my opinion, but if you are to have user's accessing there own information from the payroll system, you should provide the utmost security as possible, because if say John Doe was to enter your system and some gain access to the payroll system itself, then they can add themselves in and start being paid, plus not to mention all personal information is stored there too.

I'd say protect the website with a cert, real cert, not a self signed cert. Packet filtering would be good to have and maybe a proxy server? If this is for a company of 50,000, you might also want to think about having another layer of security on the webpage (i.e. Two Factor Authentication).

[DannyJ7]

Regarding replication, are you saying that I would replicate the SQL database to the remaining three web servers, or that I should be running four separate SQL servers in addition to the three web servers?

[DannyJ7]

I am confused right now about how to determine how many blade servers are needed. I don't have any idea what kind of load to expect, or what kind of load a typical blade server can handle.

When you talk about having three blade servers, are you talking about having three blades in a single enclosure, or three enclosures loaded up with blades?

[Septerra]

Is this payroll system a custom app or is it from a specific company? If it is from a company, you should ask them what is the specification to run the app and SQL.

From there you can make a judgment on the system that is required, then multiple it by how many you believe is required.

I am saying to have 3 seperate blade servers, to provide the redundancy/load balancing. If it was all enclosed in one system and that system happens to fail then it's pretty much useless.

As for the SQL, you will need to see how much load one SQL server can handle, and then figure out from there what is required to prevent overloading the SQL with queries and what not.