ZyXel USG20-W - internet failing and VPN issue.

JanSery

Hello, I am running quite old ZyXel USG20-W with latest firmware (upgraded today) and I started experiencing some issues couple days ago. We had internet connection outages while downloading big updates and so on. So we changed internet provider and swaped from 40Mb internet to 100Mb internet connection. We are now able to download large file without interupting rest of our Office but we have another issue. When we copy large files (8 - 35GB) thought IPsec VPN (there is only one tunnel) to our company internet connection fail, copy of files crashes (it is running during night time). I started to copy files now, ping to GW (USG20-W) is between 30 - 60ms and to internet between 50 - 120ms. I wanted to check ZyXel via web interface but it is not loading login page. I tried SSH also, but it is not able to connect. I tried ping from server (to which data are copied via IPSec tunnel) to internet and it works, but DNS is not translating while data copy on mentioned server (DNS is fine on other assets while data copying, DNS is ZyXel and second one is google).Do you think that our USG20-W is at the limit of service life? I would say it should be able to load login page at least. When we are not downloading login page works fine and SSH also. There is only FW running, no security features are on.

Thank you.