So you drew the short straw and you're on deck to support the network from December 24th-Jan 1st.
First - Sorry, that's a drag.
But, it's also a great time to do some much needed network baselining, documentation, and troubleshooting. So while you are sitting at work recovering from your egg-nog hangover, take advantage of the fact that there is minimal traffic on the network, server use is low, and most of the users are gone. In a word:
It’s time to get a fresh baseline. Not only because of the lower network usage, but because it’s a great way to go into the new year, when new problems, expansions, upgrades, and rollouts are bound to occur. Who really has time for a baseline once things go into full swing in 2013?
So what is involved? Most network baselines involve creating a fresh inventory of network devices and analyzing the traffic going through them. Since most people are out of the office, the traffic analysis won't include much user traffic. But in this case, we will talk about what to set up so when the users come back, you have the right tools in the right place.
1. Network Discovery – What is out there and how is it connected? Get a good map going of switch connectivity, server connectivity, virtualized server distribution, printers, AP’s, and phones. What switch and port are all of these connected to?
2. Compile Infrastructure Documentation – Document the software version and configuration for all switches, routers, firewalls, and AP’s. This is great to have when a problem strikes.
3. Throughput Testing – Run throughput tests on major network paths (client to server farm links, and remote office WAN links). Since network traffic is low, these throughput tests won’t impede other competing traffic. Keep in mind though that if any users really are there, they may experience reduced network performance while these tests are in progress.
4. Traffic Measurement and Analysis – An ‘Any Given Monday’ baseline will include average use of WAN links, Data Center connections, as well as internet usage. Since users aren’t there to take up the bandwidth, it’s a great time to identify where traffic flows, and put TAPs or SPANs in place (ideally taps) so these measurements can be made once the users return. Another route would be to use flow based analysis, which could be configured and collected while users are away.
Once users are back, measure network and internet usage including:
- Utilization (Average and peak)
- Top Protocols and Applications in use
- Top Users and Bandwidth Hogs
5. Check Network Management Systems – Make sure these tools are in place, upgraded to the latest versions, and configured to monitor the important network components. This includes key switches, application response time on servers, and checks to DNS and DHCP services.
So don’t just kick back and burn through YouTube videos if you happen to be working during the slowest time of the year. Take advantage of the downtime and baseline!
Author Profile - Chris Greer is a Network Analyst for Packet Pioneer. Chris has many years of experience in analyzing and troubleshooting networks. He regularly assists companies in tracking down the source of network and application performance problems using a variety of protocol analysis and monitoring tools including Wireshark. When he isn’t hunting down problems at the packet level, he can be found teaching various analysis workshops at Interop and other industry trade shows. Chris also delivers training and develops technical content for several analysis vendors. He can be contacted at chris (at) packetpioneer (dot) com.