Network Troubleshooting 101
The following article is intended to provide troubleshooting guidance for basic networks where 1 router and 1 or more switches are used for communication. I provide dmarc for msp industry best practices as well as my own experience and expertise.
Basic Network Components:
ISP Broadband Modem
Router with WAN and LAN interface
Devices (computers, servers, phones printers, etc)
ISP Modem: Is the device provided by your Internet Service Provider (ISP) that allows you to connect to their communication lines to get internet access. Usually cable providers do the wiring installation and install a cable modem at your premises. For services such as DSL you might have to provide the modem yourself. Another variation would be the Smart Jack your ISP installs in the Dmarc when using T1 lines.
Router: A router is a device that directs traffic to the appropriate destination. It is normal for a small business router device to perform other functions such as DHCP, Firewall, WebContect Filtering, etc. For the sake of this article we’ll keep routers doing their basic routing function and the DHCP service.
Ethernet Switch: Or simply a switch, it’s the device links the network devices.
Devices: anything that connects to the network.
Step 1. Verify the Problem really exists.
Make sure that the problem is real and not a user or application issue. I’ve seen this countless times when a user complaints about the network is not not working and it’s simple as simple as the user never clicking on the send button to send an email.
Step 2. Identify the Problem.