Email Notification - OpenVPN Client Connect (Common Name)

Stewart

I know this thread is kinda old but I don't know that starting a new topic is the best course of action. I'm trying to implement this but there is a delay of a couple of minutes on the disconnect script and the connect script won't log if it's waiting for the disconnect script.

In the Advanced Configuration -> Custom Options I have:

I've modified the scripts to both send an email and output to a log file when run. When a client connects, I see the log file updated immediately and the email comes very quickly. When a client disconnects it takes 2 -2.5 minutes before the log file is updated and the email is sent. During that window of time if I reconnect it doesn't log or send an email. There is very little difference in the two scripts at this point as I try to narrow down the issue.

Does anyone have any idea what this delay is and what's going on?

Gertjan

@stewart said in Email Notification - OpenVPN Client Connect (Common Name):

kinda old

Nothing changed.

My /root/notify.sh file :

#!/usr/local/bin/php -q
<?php
	require_once("/etc/inc/notices.inc");
	$local_connect_value = " user_name: " . getenv('common_name') . " vpn_client_ip: " . getenv('ifconfig_pool_remote_ip') . " on " . date('F j, Y, g:i a');
	log_error("About to send a mail : Connecting");
	notify_all_remote($local_connect_value);
?>

The disconnect.sh file :

#!/usr/local/bin/php -q
<?php
	require_once("/etc/inc/notices.inc");
	$local_connect_value .= ", during : " . getenv('time_duration') . " seconds, received : " . getenv('bytes_received') . " bytes, send : " . getenv('bytes_sent') ." bytes. DISCONNRECTED.";
	log_error("About to send a mail : Disconnecting");
	notify_all_remote($local_connect_value);
?>

The files :

ls -al *.sh
-rwxr-xr-x  1 root  wheel  353 Sep  8 08:13 disconnect.sh
-rwxr-xr-x  1 root  wheel  316 Sep  8 08:14 notify.sh

I connected to my pfSense VPN server, and disconnected a couple of seconds later.

My centralized syslog server showed :

...
2021-09-08 08:21:32	User.Error	pfsense	1 2021-09-08T08:21:35.264334+02:00 pfsense.my-network.tld php 15669 - - /root/notify.sh: About to send a mail : Connecting
2021-09-08 08:21:35	User.Error	pfsense	1 2021-09-08T08:21:37.728863+02:00 pfsense.my-network.tld php 15908 - - notify_monitor.php: Message sent to my-gmail@gmail.com OK
....
2021-09-08 08:21:49	User.Error	pfsense	1 2021-09-08T08:21:52.325734+02:00 pfsense.my-network.tld php 16254 - - /root/disconnect.sh: About to send a mail : Disconnecting
2021-09-08 08:21:51	Daemon.Warning	pfsense	1 2021-09-08T08:21:54.188458+02:00 pfsense.my-network.tld radvd 93362 - - sendmsg: Permission denied
2021-09-08 08:21:56	User.Error	pfsense	1 2021-09-08T08:21:58.979760+02:00 pfsense.my-network.tld php 15908 - - notify_monitor.php: Message sent to my-gmail@gmail.com OK
....

You can also use a console or SSH session, and execute :

tail -f /var/log/system.log

to see real time system log events.

Logs lines showed up instantly.
I received the mails.

Stewart

@gertjan said in Email Notification - OpenVPN Client Connect (Common Name):

@stewart said in Email Notification - OpenVPN Client Connect (Common Name):

kinda old

Nothing changed.

I only mentioned it because I'm always wary of necroposting and people getting upset. I'm sure it isn't the scripts themselves. Even if I have client-connect and client-disconnect call the same script the delay is still there. Would it matter if the OpenVPN server is set to Remote Access (SSL/TLS + User Auth) and authenticated by the Active Directory?

Gertjan

@stewart said in Email Notification - OpenVPN Client Connect (Common Name):

Even if I have client-connect and client-disconnect call the same script the delay is still there.

I was using the same file for the connect / disconnect event, but @bingo600 has a point - see above.
The OpenVPN connect and disconnect are instantaneously for me.

I'm using myself SSL/TLS only.
Authentication (using AD) only happens when the user logs in.

Stewart

@gertjan

I'm using different scripts for each event but tried it with the same script to rule it out.

Stewart

Progress! I've found that if I add
explicit-exit-notify
to the client then it populates immediately. I guess that without it then it's waiting for a timeout period before it disconnects the session.

Since we have a lot of clients out there already, is there a way to add this to the VPN server config? Or does it have to be manually entered into every client? I've tried adding into the server Custom Options but it doesn't work.

Gertjan

@stewart said in Email Notification - OpenVPN Client Connect (Common Name):

Progress! I've found that if I add
explicit-exit-notify
to the client then it populates immediately.

Client ?
These are OpenVPN server 'custom' command options.
At least, they are in the context of this forum thread.
You can see the doc here : https://build.openvpn.net/man/openvpn-2.5/openvpn.8.html

You are using OpenVPN 2.5.x, right ? And UDP tunnnels ?

@stewart said in Email Notification - OpenVPN Client Connect (Common Name):

I've tried adding into the server Custom Options but it doesn't work.

As above, see again :

JeGr

@stewart said in Email Notification - OpenVPN Client Connect (Common Name):

Progress! I've found that if I add
explicit-exit-notify
to the client then it populates immediately. I guess that without it then it's waiting for a timeout period before it disconnects the session.

It is. For UDP clients you have to wait your configured timeout period (normally ~60-90s) for the disconnect script to get executed as the server doesn't see the client disconnecting. Explicit-exit-notify on the client fixes that by alerting the server of the clients disconnect wish.

Gertjan

@jegr Aha !! I get it.
I was disconnecting manually my client, by sliding the on/off button in the client while testing.
That probably makes the sending a "connection down" to the server, so there were no delays for me doing such a test.

When the client looses the connection because of bad data reception (Wifi or data carrier like 4G5G) then the server would apply a wait period before it fires a "client-disconnect" cmd.

@JeGr Thanks for making that clear.

JeGr

@gertjan said in Email Notification - OpenVPN Client Connect (Common Name):

I was disconnecting manually my client, by sliding the on/off button in the client while testing.

Yes, but without explicit-exit-notify UDP clients don't inform the server of their disconnect. So the server just stops getting traffic, waits for the tiemeout/keepalive time and then internally de-registers the client as unavailable/disconnected and runs the script.
TCP clients don't have that problem because of TCP (d'uh! ;)) and explicit-exit-notify brings that to UDP - but with its own problems (e.g. mixed style multi-configs with udp&tcp remote statements for automatic fallback etc. aren't possible ATM).

As I did a bit of an updated version of that script for noplan, I tested around that myself and could see that behavior every time. One just has to be patient :)

Cheers
\jens

Gertjan

@jegr said in Email Notification - OpenVPN Client Connect (Common Name):

Yes, but without explicit-exit-notify UDP clients don't inform the server of their disconnect

See above what I have in the custom options.
My connection plain vanilla : is UDP based, port 1194 etc.

I connect, I wait 20+ seconds, and then I slide the connection connection on my iPhone - OpenVPN Connect App to off, I see this line immediately in the pfSense OpenVPN server log :

You can clearly see the 25 seconds delay.

gmail also notifies me immediately on both events.

Stewart

@jegr said in Email Notification - OpenVPN Client Connect (Common Name):

@gertjan said in Email Notification - OpenVPN Client Connect (Common Name):

I was disconnecting manually my client, by sliding the on/off button in the client while testing.

Yes, but without explicit-exit-notify UDP clients don't inform the server of their disconnect. So the server just stops getting traffic, waits for the tiemeout/keepalive time and then internally de-registers the client as unavailable/disconnected and runs the script.
TCP clients don't have that problem because of TCP (d'uh! ;)) and explicit-exit-notify brings that to UDP - but with its own problems (e.g. mixed style multi-configs with udp&tcp remote statements for automatic fallback etc. aren't possible ATM).

As I did a bit of an updated version of that script for noplan, I tested around that myself and could see that behavior every time. One just has to be patient :)

Cheers
\jens

My problem with being patient is that while waiting no other script will launch. So if someone connects or disconnects within that 90 second window (or whatever that window may be) the scripts don't launch. At least, that's what it appears is happening. I don't see a reason why it would be that way, though.

noplan

@stewart said in Email Notification - OpenVPN Client Connect (Common Name):

while waiting no other script will launch. So if someone connects or disconnects within that 90 second window (or whatever that window may be) the scripts don't launch.

r u sure ?
cuz we don't see it ... have tested after reading your post ... can't confirm it.
brNP

Stewart

@noplan said in Email Notification - OpenVPN Client Connect (Common Name):

@stewart said in Email Notification - OpenVPN Client Connect (Common Name):

while waiting no other script will launch. So if someone connects or disconnects within that 90 second window (or whatever that window may be) the scripts don't launch.

r u sure ?
cuz we don't see it ... have tested after reading your post ... can't confirm it.
brNP

Maybe it's because I'm using the same user over and over to test? When I connect the first time the log gets generated (I have the script writing to a log file instead of emailing). After that, I can connect and disconnect and no other lines are written to the log file. Not even the first disconnect gets written. If I wait until after the disconnect line gets written then I can connect and the line gets logged.

noplan

@stewart

sounds interesting

a) use a 2nd user
b) connect with user 1
c) connect with user 2 when user 1 is connected
d) disconnect user 1
e) shortly after done d) disconnect user 2

both users are written in your file ?

be so kind and show us logFile and script
brNP

Armstrong

@stewart

Are you perhaps experiencing the same thing I was in this post https://forum.netgate.com/post/897352 ?

The disconnect lags well behind the actual disconnection.

Stewart

@noplan said in Email Notification - OpenVPN Client Connect (Common Name):

@stewart

sounds interesting

a) use a 2nd user
b) connect with user 1
c) connect with user 2 when user 1 is connected
d) disconnect user 1
e) shortly after done d) disconnect user 2

both users are written in your file ?

be so kind and show us logFile and script
brNP

I'll get a second pc up and running to test with. It'll take a few.

Stewart

@armstrong said in Email Notification - OpenVPN Client Connect (Common Name):

@stewart

Are you perhaps experiencing the same thing I was in this post https://forum.netgate.com/post/897352 ?

The disconnect lags well behind the actual disconnection.

Yes and no. Yes, I'm experiencing it and it can be resolved by adding explicit-exit-notify to the client. No, in that the issue I'm dealing with is that during that delay it seems like no scripts are running.

noplan

for me this whole case is pretty interesting
because we're using this script like a ton of admins too to get information on the openVPN usage
and noOne except @JeGr (as always ) was looking for

but without explicit-exit-notify UDP clients don't inform the server of their disconnect

so plz keep us posted with all the details you got
NP

Stewart

@stewart said in Email Notification - OpenVPN Client Connect (Common Name):

@noplan said in Email Notification - OpenVPN Client Connect (Common Name):

@stewart

sounds interesting

a) use a 2nd user
b) connect with user 1
c) connect with user 2 when user 1 is connected
d) disconnect user 1
e) shortly after done d) disconnect user 2

both users are written in your file ?

be so kind and show us logFile and script
brNP

I'll get a second pc up and running to test with. It'll take a few.

I can confirm that the logging only affects that account. I simulated with a second PC. Had it connect and then disconnect. While waiting, I had the first machine connect and disconnect. It shows all of the logs as expected. It seems the lack of processing is limited to that one account.