DHCP Server: Manual or Auto?

[JT Strickland]

I apologize if this has been answered, but I have read conflicting posts about this.

Is there an advantage to manually entering local IP addresses for clients, other than preventing it from changing? Is there a disadvantage to this approach, i.e. does it make the router work harder? I have reserved below 192.168.1.20 but haven't used them yet because I don't know which way is best. I shouldn't have over 25 clients on our little network. I've never seen the router assigned addresses change that I can recall, so it may be a moot point, although I imagine they could.

What do you say?

thanks,
jts

RT-AC86U w/ 384.17, RT-AC68U Aimesh node w/ same, Diversion, UiDivstats, Skynet, AiProtection, DoT, Scribe, UiScribe, Conmon, SpdMerlin, ScMerlin, Nsrum, NtpMerlin, OpenVPN selective clients

 

[Ronald Schwerer]

There's negligible overhead for the DHCP server to look-up the MAC and assign a fixed IP. There's benefit if you actively manage your LAN. For example, I don't want my APs, nodes, and repeaters IP addresses moving - I log-in often. I have scripts with the hard-coded IP.

Also by assigning fixed IPs to my clients I can easily see when something unknown shows-up in the client list. Then I investigate to see what it is. If I can't figure it out, I block the MAC and see if something stops working. If I still can't figure out who/what it is - I leave it blocked.

 

[CaptainSTX]

With your AC86 you have a larger NVRAM memory capacity. For those using older routers with less NVRAM static IPs use some portion of NVRAM so depending what other features they use NVRAM capacity can be exceeded.

 

[David Cavalli]

I have an RT-AC68U. I now generally have 5+ computers and 20+ devices on at all times. When I used the Asus Merlin GUI to allocate my IP addresses, it worked great until I had so many new smart devices that my NVRAM memory was all but gone. I ran some NVRAM cleaners and it almost bricked my router. In order to maintain static web pages for my smart devices, I really wanted to fix the IP addresses for most devices locally online.

The best solution to resolve my NVRAM vs. allocation issues was to use the dnsmasq.conf.add file in /jffs/configs. This file uses minimal NVRAM yet maintained my MAC->IP reservation desire. Highly recommend this solution. I was even able to add graphics to the web page for each device and still use less NVRAM then when I first bought this router 4 years ago and had only 6 devices.