Issue with VPN connections

SERENiT

I have a Zyxel VPN50 with several IPSec VPNs with following appliances on the other side:

• ZyWALL USG 20(W)
• USG FLEX 50 (USG20-VPN)
• PaloAlto (I don't know exactly which version)

All these VPNs were working fine since monthes, but suddenly 2 weeks ago we started having VPN connections dropping; then we also started facing situations where the VPN connection is up but the traffic doesn't go through it.

I have installed the latest firmware (5.36(ABHL.2)) on the central one and on the USG FLEX 50 (5.36(ABAQ.2)) but I cannot do any upgrade on the ZyWALL neither on the PaloAlto and the VPN connections with these models doesn't work (it is up but traffic doesn't pass).

What can I do to recover the situation?

Thanks

Zyxel_Jeff

Hi @SERENiT

Welcome to the Zyxel community. What is your current running firmware version of ZyWALL USG 20(W)? The VPN connection issues might be caused by a Buffer overflow issue, so we suggest you can update the firmware to the latest version and see whether it is working for you. If you still have problems, please let us know. Thanks.

https://community.zyxel.com/en/discussion/17102/buffer-overflow-issue-faq

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