FortiClient VPN issue

[RenatoM]

Hi all,

I am using FortiClient VPN to connect to Company network.

Last week we changed our internet provider and with this we changed our IP address.

In configuration of FortiClient VPN we setup server value as https://subdomain.our.domain . We changed DNS settings for this value to new IP and if I ping subdomain.our.domain I am getting correct IP address.

But, my FortiClient is always trying to connect to old IP and I get error "The response from:
https://my_OLD_IP was invalid."

If I reinstall FortiClient VPN then he will delete everything and Client will start to connect to correct address and everything will work. So he will start to resolve correct IP address.

My question is: Is there some way to delete this value without reinstalling FortiClient?

Also, if someone have experience with iMac devices - Uninstalling client is not helping with this.

[btan]

Hi RenatoM,

Have you tried delete the configured tunnel and add a whole new connection?

[RenatoM]

Yes. This was first thing which I tried. 

[akumarr]

Dear RenatoM

May I know whether the issue is happening for a specific Forticlient version?
Could you please remove the complete Forticlient using this tool?
https://kb.fortinet.com/kb/documentLink.do?externalID=FD40369

And then try using a different forticlient version, post that try adding old IP and add the new one and verify the behavior.

[RenatoM]

Dear akumarr,

this is what I am trying to avoid - uninstalling FortiClient. I know how to uninstall and after uninstalling everything is working. 

My question was is there a way to avoid uninstalling? To delete some cache or something. 

Thanks!

Renato

[vsahu]

Hello RenatoM,

* Take a Wireshark capture when connecting with Forticlient and check if the machine is even probing for DNS or not for the FQDN,

* Try adding host entry on the machine and check the behavior 

[vsahu]

Hello RenatoM,

Also, try flushing the DNS on  the machine and check
ipconfig /flushdns

[RenatoM]

Thank you all but still no luck. 

For now results are:

- Windows devices - reinstall of FortiClient help (but I would like to avoid reinstalling)

- Mac devices - no luck even if I reinstsall FortiClient.

When I ping my hostname  i got correct IP in shell.

I also added hostname with correct IP to HOSTS file on Mac - no luck. FortiClient still resolving old IP.

FortiClient version 7.0.7.0245

macOS Monterey 12.5.1

Any other ideas?

[vsahu]

Hello RenatoM,
Have you checked on the windows machine with flush DNS is it working for you?

ipconfig /flushdns

[RenatoM]

Yap. One of the first things.