Do you have a network printer, network drive, or other network device that works most of the time but sometimes becomes unavailable suddenly? Then, for no reason it comes back online again?
I had this exact experience just recently at a customer’s location. I walked in the door just as one of the printers stopped working.
The solution might not be what you think.
It Was My Phone
Turns out when I walked into the customer’s location my phone tapped into the local WIFI for the company and this caused the printer to go offline.
Why? It all has to do with assigning IP addresses in the network and this is done usually on a router or server using DHCP (Dynamic Host Configuration Protocol)
The Importance Of DHCP Ranges
A networked printer means that the printer is assigned an IP address. The best way is to assign a static IP directly on the printer. However if you do this then you must keep in mind the dynamically assigned IP range – which is managed by DHCP. By default on a router this range is usually something like 192.168.1.100 – 192.168.1.149.
If you give your printer an IP that is also within that range then you definitely run the chance that the router will assign the same IP to somebody else, and this will cause both devices to stop communicating properly.
Here’s 2 Options
1. change the printer IP to something that is outside the DHCP range, or
2. Make a “reservation” of the IP of the printer. Many routers and server allow you to reserve an IP within the DHCP range for something specific. I don’t recommend this method, I much prefer option 1.
Map Your Network
For my customers I assign different IP ranges for different devices. For instance I may do something like this:
- 192.168.1.20 – 29 All networked Printers
- 192.168.1.30 – 39 All servers
- 192.168.1.40 – 49 All routing equipment
- 192.168.1.100 – 149 All dynamically assigned IP’s (DHCP)
Most “users” of the network never think about connectivity, it just works. However as a tech I always want a logical managed environment, one that makes it easy when I purchase a new printer to know exactly where to put that on the network because it has an assigned IP range. This makes the whole job of managing and troubleshooting the network easier.
It also means that when something drops off the network and becomes unavailable all of a sudden I know where to look.