VPN SSL DROP AFTER OPEN A RDS SESSION

ELI

Hi,
my customer use zywall secuextender to connect to a VPN 100
the vpn connection work fine but if he want to connect his RDS session, THE VPN DROP

here is the log
[ 2024/09/16 17:21:29 ][SecuExtender Agent][DEBUG] Virtual network interface: \.\Global{AF359EC3-B88B-4562-82EF-CD6AC01BF5CF}.tap
[ 2024/09/16 17:21:29 ][SecuExtender Agent][DEBUG] TAP-Windows Driver Version 9.9
[ 2024/09/16 17:21:29 ][SecuExtender Agent][DEBUG] TAP-Windows MTU = 1370
[ 2024/09/16 17:21:29 ][SecuExtender Agent][INFO] security tunnel is created!
[ 2024/09/16 17:21:29 ][SecuExtender Agent][DEBUG] Entering main loop
[ 2024/09/16 17:21:29 ][SecuExtender Agent][INFO] GetOverlappedResult success, agentState.aState = 2, agentState.aError = 0, dwReadBytes = 8
[ 2024/09/16 17:21:29 ][SecuExtender Agent][INFO] GetOverlappedResult success, agentState.aState = 3, agentState.aError = 0, dwReadBytes = 8
[ 2024/09/16 17:22:01 ][SecuExtender Agent][ERROR] Connection to ZyWALL is going to be shut down. (0x0)
[ 2024/09/16 17:22:01 ][SecuExtender Agent][DEBUG] SSL Connection is going to be closed
[ 2024/09/16 17:22:01 ][SecuExtender Agent][INFO] Connect to 37458558:7043
[ 2024/09/16 17:22:01 ][SecuExtender Agent][INFO] Local address is 3232254769
[ 2024/09/16 17:22:01 ][SecuExtender Agent][DEBUG] Connect success.
[ 2024/09/16 17:22:01 ][SecuExtender Agent][DETAIL] Handshake LoopCounter: 0
[ 2024/09/16 17:22:01 ][SecuExtender Agent][DETAIL] 1274 bytes of handshake data received
[ 2024/09/16 17:22:01 ][SecuExtender Agent][DETAIL] InitializeSecurityContext returns 0x90312
[ 2024/09/16 17:22:01 ][SecuExtender Agent][DETAIL] Send 93 bytes of handshake data
[ 2024/09/16 17:22:01 ][SecuExtender Agent][DETAIL] Handshake LoopCounter: 1
[ 2024/09/16 17:22:01 ][SecuExtender Agent][DETAIL] 51 bytes of handshake data received
[ 2024/09/16 17:22:01 ][SecuExtender Agent][DETAIL] InitializeSecurityContext returns 0x0
[ 2024/09/16 17:22:01 ][SecuExtender Agent][DETAIL] SSL Handshake is successful
[ 2024/09/16 17:22:01 ][SecuExtender Agent][DETAIL] STREAM_SIZE: Header: 13 Trailer: 16, MaxMessage: 16384
[ 2024/09/16 17:22:01 ][SecuExtender Agent][INFO] logout message has sent
[ 2024/09/16 17:22:01 ][SecuExtender Agent][DEBUG] SSL Connection is going to be closed
[ 2024/09/16 17:22:01 ][SecuExtender Agent][DETAIL] Connection ends.

The MTU is 1370

Zyxel_Kay

Hi @ELI

To better understand your case, we need some additional information. Could you please provide the following details?

1. What are the current firmware versions for the VPN100 and the SSL VPN SecuExtender client that your customer is using? We recommend updating both to the latest versions to see if this resolves the issue. The latest firmware for the VPN100 is 5.37(ABFV.2) and the latest SSL VPN client version is 4.0.5.
2. Could you specify the RDS scenario your customer is experiencing? For example, are they using Windows RDP, VNC, or another protocol?
3. Can you collect packet data from the PC side when the SSL VPN session drops? This will help us determine if the issue is related to the firewall or the PC.
4. Could you provide the firewall's startup-config file?

For security reasons, please send the packet capture and configuration file via private msg.

Thank you!