@David-TP 

The DECOs get semi-static IP from my router via DHCP lease, so there isn't any problem - I use it for some other devices too. All other devices have no problem with loosing internet connectivity. Please note that all three units are connected via ETH backhaul.

Currently I got some idea based on fact that the issue seems to occur only via night - I've disabled the status LEDs for night. Will try to reproduce the issue in next days(nights)

Regarding syslog - is there some possibly to collect the messages via some software?

/BR

ZoloN

  @David-TP 

Hi David,

here my newest observation:

when going mad - the log is full of

• up/down events for eth0, eth0.1, eth0.2
• daemon.warn awn[1453]: [awnd_update_lanip:1563]: get lan ip failed

and - what is the most important stuff:

• user.notice smartip: [lan] start udhcpd
• and the Main DECO provides random IP addresses to clients even if in AP-mode causing duplicate IP addresses on the network
  • daemon.err udhcpd[25383]: Sending OFFER of 192.168.33.1x

/BR

ZoloN

  @ZoloN 

Have you installed beta firmware TP-Link Support sent you? It is supposed to fix "the Main DECO provides random IP addresses to clients even if in AP-mode" and might also fix remaining issues that arise from this.

  @Alexandre. 

As an IT-Pro I would like try to find the root cause - installing beta firmware should be the last solution. IMHO my issue isn't in status "known issue", as when I tried to open a support ticket - outcome was they have suggested warranty replacement of devices...

  @David-TP 

unfortunately, I'm unable to get the logs from main DECO covering the outage time, therefore I ask again: is there any possibilty to forward the syslog messages automatically to a computer?

what I can now confirm - the scheduled turning off the LEDs is not causing the problem - I've turned the feature off - problem persists.....

My ISP (A1 xDLS) has regular approx 1-2 minutes long outages always around 3:00 a.m. - and those are causing a problem. if there is an outage durring day/afternoon/evening - absolutely no problem.... (has the FW problem with single digit hour / starting with zero?)

another question: on DE/AT sites is the latest FW still 1.5.8, but on global or UK 1.6.1 - dated 02.02.2024 - are the changes from mentioned beta indide? should I go for 1.6.1 or stick to regional one? (and is there newer beta as 1.5.4?)

/BR

ZoloN

ZoloN wrote

  @Alexandre. 

As an IT-Pro I would like try to find the root cause - installing beta firmware should be the last solution. IMHO my issue isn't in status "known issue", as when I tried to open a support ticket - outcome was they have suggested warranty replacement of devices...

 

  @ZoloN 

Well, then I can talk as an IT-Pro to an IT-Pro.

What you have might be related to Smart DHCP feature in AP mode: Main Deco will turn on its DHCP service when there is no DHCP server present.

That could happen when ISP router restarted or bounced. In most cases, Smart DHCP feature does not cause any harm: as soon as ISP router back online, Deco dhcp service turns off. IP addresses distributed by Main Deco are in IP range of ISP router and have very short Lease Time, under 2-3 minutes. Even if device managed to get IP address from Main Deco during ISP router downtime, it will promptly renew it very soon after ISP router is back and will get IP from the router.

The problem arises in cases when ISP router also has Smart DHCP feature: "do not start DHCP service if another DHCP server is already active." After ISP router comes back online, it realizes there is DHCP server (Main Deco) and won't start its own service. The havoc follows.

Beta firmware TP-Link Support suggested to install has option to turn Deco Smart DHCP service off, thus eliminating collision between ISP router and Main Deco.

GA firmware version 1.6 and up has option to turn Deco Smart DHCP service off through Deco app.

-----------------

To verify that Smart DHCP is the cause of the issue: power off ISP router for about 5 minutes, then power it on. If you observe networking problems after ISP router comes back- that must be it. Additional verification: on networking device (PC, smartphone, etc) renew its IP lease and after that check what does it report as DHCP server and default gateway. If you see IP address of Main Deco as DHCP server (and possibly as default gateway) - that is Smart DHCP in play, for sure.

To fix that issue when it happens, on Deco firmware 1.5: power off Main Deco and all Ethernet wired Satellite Deco. Satellite Deco using WiFi backhaul may stay on (or you could power them off also, just to be sure). Bounce ISP router (just in case). When ISP router is fully online - start Main Deco. When Main Deco is fully online - check DHCP and default gateway IP addresses on networking device. As long as you see ISP router IP address there - everything is recovered and you can now power on Satellite Deco.

Note that shutting down Satellite Decos on Ethernet backhaul is important step that should not be skipped.

  @Alexandre. 

thank for your description, was very helpful - mystery is most probably solved:

• when there is a "real" intternet outage, all is fine - as internal DHCP is present
• I've completely forgot, that approx. 1 year ago I've scheduled a weekly reboot of my router on monday at 3:00 a.m.

I'm going to intall the 1.6.1 FW and will see what happens. will report shorly

/BR

ZoloN

  @Alexandre. 

FW upgrade to 1.6.1 was successful. Unfortunately, I can't find the settings to turn off the Smart DHCP in App nor webUI...

/BR

ZoloN

  @ZoloN 

With GA firmware 1.6 this can be found under Advanced in Deco app:

It is possible that in beta firmware it is hardcoded. Try to reproduce the issue to check that. If Smart DHCP is now disabled, after you power off ISP router and renew IP lease on device connected to Deco mesh, that device should NOT report Main Deco IP as its DHCP server. Device will fail to obtain new IP address if Smart DHCP feature is turned off.

  @Alexandre. 

In my Android App (version 3.7.5) I can see only following:

FW is 1.6.1 Build 20231227 Rel.80438