Zyxel nebula dashboard says switches are offline

Lorcan

Hi guys,

I believe my problem turned out to be that the switches were in static mode (192.168.1.10 - 192.168.1.13) and I had bought a new router which was 192.168.88.1. As the switches weren't in DHCP but rather static, they couldnt receive an IP from the router.

There is also an option called 'Cloud-saving' mode which will disable all info in the Nebula control center so make sure thats turned off.

This fixed my problem but of course you guys may have some other problem I dont know.

Zyxel_Melen

Hi @MarkSL,

Please help to check the below item:

1. Does the switch have an IP address?
   You can verify with ZON.
2. Can the switch access the default gateway and the internet?
   Please login to the switch and ping the default gateway and the internet to verify.
3. Can the switch resolve d.nebula.zyxel.com?
   Please login to the switch and ping d.nebula.zyxel.com to verify whether it can resolve this domain or not.
4. Does the firewall/router/modem block the Netconf protocol?
   Please allow port 4335 and 6667 which are used to communicate with Nebula.
5. Does the firewall/router/modem change the MTU size?
   Changing the MTU size might cause the device offline, please make sure the MTU size is not smaller than 1500.
   

MarkSL

This is currently not an issue. A hands-on reboot would normally clear the issue. This is not an issue with configuration, the switches will simply never move to DNS2 if DNS1 is not responding. And often even when DNS1 returns, it will never refresh. Note, the switches work fine during this time, all devices connected to the switches have no issues. The switches are just not checking into Nebula.

Zyxel_Melen

Hi @MarkSL,

Thanks for your reply, but when the DNS1 is unreachable, the switch will change to the backup DNS (8.8.8.8) to resolve the domain. If the problem occurs again, could you provide switch tech support for me to verify?

MeatPopsicle

I have the same issue. Switches are operational but show as offline in Nebula console. Devices cannot be accessed via local web GUI as Nebula enrollment disables the local interface. Is my only option to factory reset the devices?

MarkSL

In most cases, a reboot cleared ours but we have had 2-3 times a default was required.

Zyxel_Melen

Hi @MeatPopsicle,

Please reference this FAQ to troubleshoot the switch offline problem.

How to simply troubleshooting on my Nebula Switch?

Zyxel_Jason

Apr 21, 2020

Hi all Nebuler~

We create a guide for you guys to have simple troubleshooting steps when you encounter a problem on Nebula Switch.
We will keep updating more symptoms to the file in the future.
Please stay tune on this post. 

Thanks.

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If the problem remains after troubleshooting, please help to enable Zyxel support and help collect the switch tech support for me to check.

The tech support can be collected by accessing the switch local GUI: Menu > Management > Maintenace > tech support. The login password can be found on Nebula control center: Configure > Site settings > device configuration > local credentials.

Ricardo_ITS

I am having the same problem.
Switch GS1920-48v2 appears offline in Nebula. If I change it to another internet line, in my house for example, it appears online.

But in my company network, the firewall does not have any limitation towards the switch, even I have opened the ports 123-4335-6667 as I have read and it does not receive any communication from those ports.

The ip addresses and the dns are well placed as far as I can see in the ZON.

I don't understand what could be the problem.

Zyxel_Melen

Hi @Ricardo_ITS,

Could you help to access the switch web GUI to collect the tech support for me to check? The path is Maintenace > Tech-support > all. And please provide it to me via private message.

Ricardo_ITS

Sure, here is the file generated. Thanks