Fixed IP, changed after a while back to DHCP

[dverleysen_151162104025310]

Hello,


I have set my camera's IP addresses to fixed several times, but after a week or more, they change back to DHCP and receive a new IP address.
Other devices on my network do not have this issue. The NVR with one connected camera retains the fixed IP address, but the other three cameras connected to the home network keep changing back to DHCP instead of keeping the defined fixed IP address.

Is it something with the config or another setting that is wrong?



Camera details
Model - RLC-410-5MP
Build No. - build 20121100
Hardware No. - IPC_51516M5M
Config Version - v3.0.0.0
Firmware Version - v3.0.0.136_20121100
Details - IPC_51516M5MS10E1W01100000001

[Crimp On_62210811129]

@dverleysen_151162104025310 Truly a puzzle. I had thought that DHCP is the process by which devices learn the address of DNS servers. No DHCP: no DNS. (My knowledge is not deep.)
Perhaps you could try specifying the DNS servers (even if you are happy using the router gateway IP, just hard code it).

I found setting Static IP on individual devices to be a chore. Most routers offer the capability to "assign" or "reserve" IP addresses by entering device MAC addresses in a table. The device thinks it is using DHCP (and it is), but every time it gets the same IP from the table.

[joseph_1979]

@dverleysen_151162104025310 It's entirely possible to mix static IP and DHCP addressing schemes. Since the default DHCP address range is between 100 and 149 (unless you changed it ... check it out), you'll want to avoid all of the addresses between 192.168.1.100 and 192.168.1.149 when you're assigning static IP addresses. That leaves the ranges from 2-99 and from 150-254 wide open, which is usually plenty for most home networks. Or else disable the DHCP of the router and have fixed IP on all devices within the same lan.

[joseph_1979]

@crimp-on_62210811129 DNS and DHCP are entirely two different things; each one of them has its purpose. Normally the DNS address is assigned the gateway IP which shall forward the DNS query.

[Crimp On_62210811129]

@joseph-chircop_497308027822318 Thanks for the explanation. The term "Auto" was a surprise. If the screen had said, "Use Gateway IP address for DNS", there would have been no doubt.

[joseph_1979]

@crimp-on_62210811129 Not always. You may directly use a public DNS such as google 8.8.8.8. The default gateway would mean that the DNS query will be forwarded to the ISP. For instance to get the A record for the p2p8 Reolink server from the google DNS server, in Windows cmd enter nslookup --dns-ip=8.8.8.8 p2p8.reolink.com Once the client receives the A record it will query each P2P server for each camera (connected ones) to get what? Guess :).

[Crimp On_62210811129]

@joseph-chircop_497308027822318
(This discussion is probably not helping understand the original issue: Static IP defined on the camera changing to DHCP,
but........)

When a Static IP is defined, the Gateway IP address must be on the same IP subnet as the camera. For consumers, this is almost always their home WiFi router. Once the Gateway gets the DNS query, it can to "whatever it wants." It could forward requests to the ISP, to Google, to CloudFlare, etc.

If the camera was set to use Google DNS (rather than "Auto") then the camera would send DNS requests to the Gateway IP address because Google DNS (8.8.8.8) is not on the local IP subnet. These requests would bypass the consumer router and ISP and go directly to Google.

Probably going in circles with this. I have no clue what could cause a camera which has been set to a Static IP to change to DHCP.

[user_623715019411529_623715019411529]

@crimp-on_62210811129 I think what everyone is answering the issue in different parts of the question. From what I can tell he only set the static ip option on the camera and not the router. If that's so you have to give the camera a static ip on the router first then through the camera app that you have posted here. Most home router don't care about the scope of the ip addresses...in the router or at least mine it lets me choose which one to apply it to along with the MAC address. For everyone reading this and Joseph you help ton's of people out as you know I had the reverse issue as the poster where the camera's were going offline and not connecting unless i power cycle them well the answer was exactly the same thing. I had the IP static on the router but NOT the camera network settings cause I'm on an NVR. Once I had the camera and router synched its been perfect for a week now. 511WA's have log files and it was the only way to find it.

[Crimp On_62210811129]

@user_623715019411529_623715019411529
That's an interesting theory, but my Wireshark captures do not confirm that. When a device is set (on the device) to a Static IP, it never makes a DHCP request of the router. This could easily lead to conflicts if the router attempts to assign that IP address to another device. Home routers definitely care about the subnet mask (if that is what 'scope' refers to). When any device on the network wants to connect to somewhere, it compares the destination IP address against the subnet mask. If the destination is in the same subnet as the sender, the sender will issue an ARP request to find the MAC address of the destination and use the MAC address to send directly to the destination. If the destination is outside of the subnet, then the device will send the packet to the gateway and say, "You find out where this destination is because it's not on the network with me."

I agree that setting Static IPs on the device is not a great thing to get into. FAR better to make the IP assignments on the router to start with. However, once the camera has been told "this is your IP", I cannot imagine what would cause it to change.

[joseph_1979]

@user_623715019411529_623715019411529 It is the client which requests the DHCP service and so if camera is set to STATIC IP then it should keep this IP. However, if it changes its IP then there is an internal mechanism during rebooting (recall that there is a scheduled reboot on the camera) which requests IP from the DHCP and if this is honoured then the provided IP will be set. I am not the firmware designer and so I cannot say with precision why the camera changed its static IP............but I think this is what is happening based on my engineering knowledge. If you can reproduce it and can share the captured trace, we can check it out.

[dverleysen_151162104025310]

@joseph-chircop_497308027822318 you're right!
I did a manual reboot via de admin console, and the connection type is back to DHCP instead of fixed IP.
Don't know if this is a bug or normal behaviour, for me it's a bug.

[joseph_1979]

@dverleysen_151162104025310 Ha ha......... In my opinion it is purely a bug. Please report it to Reolink support and tell them how to reproduce it. Don't forget to include the camera HW and firmware versions. This might be with a number of Reolink cameras.

[mabradshaw1969_699633369329701]

@dverleysen_151162104025310
We have 80 or so 410A's, another 40 or so 510A's, and 10 or so PTZ's all different models. We also have 10 or so Amcrest PTZ's. We set these REOLinks to Static for our NVR and turn on ONVIF. Once a week I open the Reolink app on my phone or my PC to find the all the cams that "reset to DHCP" on our network. I'd say anywhere from 2-5 cams a week lose their DHCP. Now, I know this isn't a "Network" issue as one, I'm a network engineer and manage large networks. We do have a DHCP scope, however the scope is outside the IP range of these cameras, we are running a /16 mask. Cams are on an entirely different /24 network all to themselves. This is a REOLink bug across severs models.

Quite annoying, but for $59 a camera, I get that they are buggy. Sad, but true.