Max L2TP over IPSec concurrent connections on USG 100

Chris20

Hi, my USG100 firewall is properly connected site-to-site ipsec tunnel with a USG20.

No other active SSL connections.

In these days of COVID-19 I activated some users in L2TP over IPSec with windows 10. The first 3 users are able to connect correctly, the fourth appears this error:

If one of the first 3 users disconnects, then the other can connect.

Here https://mysupport.zyxel.com/hc/en-us/articles/360006999419--FAQ-Does-my-Zyxel-router-include-VPN-licenses- says that maximum connections are 50.

What could be the problem?

Thank you!

Chris

Nik

Hi.

Guide for this device: http://download.from.zyxel.ru/download/b7019126-4d3c-4cfd-aa20-4ccda91d4ad2/ZyWALL_USG_100_UG_v2-20_Ed4.pdf

Check number of active vpn sessions on device.

IPsec VPN and L2TP share same number of session.

Regards,

Nik

Jeremylin

Make sure the L2TP IP range is enough for clients.

I have this years ago model, what firmware version do you use?

Chris20

https://businessforum.zyxel.com/discussion/comment/13157#Comment_13157

Hi Jeremylin, thank you for reply.

IP range is enaugh , 255

I use an older firmware version, 3.00(AQQ.4)

i've tried with newer version, but there are connection problem in site-to-site with USG20.

Soon I think I will buy 2 ZyWALL VPN100, one for each site, do you think it is enough?

Chris20

https://businessforum.zyxel.com/discussion/comment/13139#Comment_13139

Hi Nik, thank you for reply.

Under session monitor i see a total users sessions number of 50.

Is this why other vpn cannot be activated?

In that case, they are not "quantity of concurrent VPN connections", but "quantity of concurrent VPN sessions".

Can I limit the number of sessions for VPN users?

Jeremylin

The firmware is not new one.
Try this version:
https://businessforum.zyxel.com/discussion/4247/zywall-usg-series-v3-30p9-wk48-firmware-released#latest