Hi @Kadybee 

Thanks for posting in our business forum.

So, nothing has been changed lately on either side and this becomes noticeable?

Can you draw one for the community about your diagram?

Config screenshots as well.

It would be totally strange if you said it has no changes on both sites or the diagram and it suddenly becomes like this.

Please mosaic your sensitive information. Here is a list of information considered sensitive:

1. Public IP address on your WAN if your WAN is.

2. Real MAC address of your device.

3. Your personal information including address, domain name, and credentials.

For troubleshooting purposes, when a WAN IP is needed, please leave some values visible for identification.

  @Kadybee 

I have experienced similar issues with draytek routers being the dialling VPN initiator into TP-Link routers.  I would see DPD failures at random, strange connectivity like you are seeing etc.

If i remember right, I was able to mostly resolve it by changing the IPsec phase 1 and 2 encryptions to the "lowest" settings the draytek supported and changing the DPD timeout.  But i never fully resolved it.

Since i switched to TP link at remote site, the VPN is never problematic.  I think its a draytek issue.

  @GRL 

Thanks for that confirmation.  I suspected as much as the TP-Link Omada based sites VPNs are as solid as.  The only reason I went with the existing Drayteks was the VDSL connection and the lack of Omada in that.  Will switch the drayteks to bridge mode I guess and see where that takes me.