HP Network Node Manager 9 : Before we Manage with NNMi (part 4) - Server sizing considerations, Licensing policy

Server sizing considerations

NNMi server sizing depends on many parameters, which sometimes cannot be precisely measured and, more importantly, doesn't give a straight answer as to which server hardware should be selected. This is a list of parameters which should be taken into account when you start sizing an NNMi server:

• Number of managed nodes

• Number of managed interfaces

• Number of managed networks

• Number of managed segments

• Number of managed VLANS

• Number of managed HSRP groups

• Number of connected ports

• Number of simultaneous users

• What iSPIs are planned to be used?

HP representatives use server sizing calculator, which is based mostly on the parameters listed previously. Calculation output, however, is not accurate. HP provides several configuration examples on their website, which were tested, and regarded this as the best source for server sizing. In the following table, there are three server sizings taken from HP NNMi documentation. According to these examples, you may decide what server hardware should be ordered for your infrastructure.

Parameter	Small	Medium	Large
Number of nodes	Up to 3K	3K - 8K	8K - 18K
Number of discovered interfaces	Up to 120K	Up to 400K	Up to 900K
Number of polled interfaces	Up to 10K	Up to 50K	Up to 70K
Number of polled node components	40K	60K	80K
Number of concurrent users	Up to 10	Up to 25	Up to 40
CPU	4 CPU cores (2.5GHz for x64, 1.4GHz for IPF or RISC)	4 CPU cores (2.5GHz for x64, 1.4GHz for IPF or RISC)	8 CPU cores (2.5GHz for x64, 1.4GHz for IPF or RISC)
RAM	8 GB	16 GB	24 GB
Java heap size	4 GB (-Xmx 4096m)	6 GB (-Xmx 6g)	10 GB (-Xmx 10g)
Disk space for application installation	5 GB	5 GB	5 GB
Disk space for database	60 GB	140 GB RAID 1+0 or 5/6 with write cache recommended (4 disk)	300 GB RAID 1+0 or 5/6 with write cache recommended (4 disk)

Remember, memory is never enough. So if you have an opportunity, size your server with more memory than you see in sizing recommendations.

Question: Which Operating System should we choose?

Answer: Personally, I have neither done detailed tests on NNMi performance, nor have I met anybody who has neglected the commonly that RISC or IPF architecture servers perform better than Intel architecture servers. Also, when you make your decision about OS, consider maintenance costs. Hardware is only a part of all your costs and I would say not the largest one. Your headache may increase if you choose OS which you are not familiar with, or have no professionals who are familiar with it. If you are a Windows guy, go for Windows. If you are more experienced with Linux, choose Linux instead. All of them work and having your favorite OS on operations will reduce MTTR (Mean Time To Repair) and probably MTBF (Mean Time Between Failures), and will increase your satisfaction working with NNMi as well.

When choosing an OS, also takes into account the iSPI you plan to use. Some of them are OS-specific and you may be forced to choose a specific OS. For example, iSPI for Multicast works only on Windows OS. Read iSPI latest release notes before you make a decision.

How NNMi will impact my infrastructure

Designing management tools, such as NNMi, are not only about sizing a server. The following are important issues as well:

• Traffic consumption by the monitoring tool

• Security policy changes in your infrastructure

• Data storage space for system backups

• Infrastructure device naming convention

Traffic consumption by the monitoring tool

When you design an NNMi system, you should also take into consideration the system impact to the whole infrastructure. For example, NNMi polls devices on a regular basis and receives SNMP traps as well. Depending on your monitored infrastructure size, polling cycle, and SNMP trap flow, you can overload your network bandwidth. Due to this, you should estimate if you can afford such traffic consumptions during system design stage.

There is no accurate traffic load calculator, as NNMi optimizes its polls grouping into SNMP query bulk reads. Using this method, it is hard to estimate traffic load. The only way to get a real number is to try it in a lab or operational environment. Traffic generated by NNMi depends on:

• Number of polled interfaces

• Polling frequency

• Data collection objects (if iSPI Performance for Metrics is used)

• Data collection polling intervals (if iSPI Performance for Metrics is used)

So, if you notice that NNMi consumes too much traffic, try reducing one or more parameters listed previously.

Security policy changes in your infrastructure

Before you start NNMi implementation, make sure your firewall has following ports opened:

• TCP Ports 80, 443, 1098, 1099, 3873, 4444, 4445, 4446, 4447, 4457, 4458, 8083, 8086, and 8087

• UDP Ports 161, 162, 696, and 45588

Antivirus software slows NNMi performance or even stops some of the functionalities. So before you start NNMi implementation, make sure that you have disabled your antivirus. This is a very important point. If you have any issues launching your NNMi server, the first thing that should be checked (after you checked whether all services are up and running)—is if you have antivirus running.

Data storage space for system backups

You will also probably design an NNMi with regular backups, which have to be stored in some external data storage. Consider a dedicated safe data storage place for your backups.

Infrastructure device naming convention

Another recommended, but not necessary, task is to make sure that your managed nodes follow your infrastructure's naming convention. There is no technical limitation and NNMi will work in either of the following ways:

• No naming convention at all

• Device names were changed after NNMi completed node discovery

• Naming convention was applied before NNMi implementation

This recommendation is about your own convenience. First of all, you will need to make sure that node names have changed in NNMi after you changed them on managed devices. Then, if you have used some long-term data for analysis, name changes will make a mess in your reports. If you have implemented some integration with third party tools on your own, you may have some integration issues if your API wasn't designed to be ready for node name changes.

Licensing policy

NNMi is licensed by discovered nodes. One node-one license and it doesn't matter whether it is a switch with several dozens of interfaces or just a workstation with one network interface. It is a good practice to design the network discovery to discover only nodes which are needed to monitor and avoid any additional nodes as much as possible, for the following reasons:

• You may reach your license limit very fast. Please be aware that unlike NNMi 7.x and its previous versions, NNMi 8.x and newer do not discover any additional nodes when the license limit is reached.

• The more devices that are being polled, the more the server is loaded. In other words, by monitoring unnecessary nodes, either the server works slower, or extra hardware is purchased for upgrades to maintain system performance.

Also, keep in mind that NNMi counts nodes that are discovered. So even if you have set a node to an unmanaged mode, it is still counted against licensing policy.

NNMi installation comes with a 250 nodes license for 30 days, and it includes NNMi Advanced and NNMi iSPI NET features for the same period of time. You don't need to reinstall NNMi if you have decided to add your permanent license on top of the trial version, even if your permanent license has the standard edition.

To check what license is installed currently, go to Help | About HP Network Node Manager i-series:

Licenses are sold by 50 node incremental, that is, if you monitor 125 nodes, you need 3 by 50 nodes licenses. As soon as the amount of your discovered nodes is over 150, you will need additional 50 nodes licenses (even if you have just one node over; that is, 151 nodes require 200 nodes licenses).

iSPIs are licensed separately and each of them has its own licensing policy. Read each iSPI's release note when you size your system or contact HP representatives if you need assistance counting required iSPI license capacity.