Application incomplete

[SOC_CSG]

Hi,

Why Palo Alto is detecting sometimes the application like SSL and sometimes like incomplete??????

if the connection has 134bytes is not detected, but with more than 134b is detected..........

[hshah]

Hi COS,

application "incomplete" means un-complete three way handshake.

Application "ssl" means firewall has seen complete three way handshake and couple of packets after that.

Now in logs you can also see "how many packets are sent and receive".

for incomplete application you will see that not more than 3 packets were exchange in two direction.

To verify it enlarge every log.

Regards,

Hardik Shah

[hshah]

Hi COS,

You can also refer bellow document.

Incomplete, Insufficient data and Not-applicable in the application field

Regards,

Hardik Shah

[SOC_CSG]

Yes i know but why the system App would start connections with less of 3 packets, thats not make sense right?

[hshah · Accepted solution]

Hi Cos,

That can be answered through packet capture or enlarged version of log.

Please provide me, it will help me with the analysis.

Regards,

Hardik Shah

[SOC_CSG]

Ok ill do a packet capture and ill let u know....thanks

[hshah]

Thanks COS ...

[MP18]

i see incomplete application with  more than 3 packtes in either direction

[LukeBullimore]

@MP18 Application incomplete can also mean that the three-way-handshake completed but there wasn't enough data afterwards to be classified into an App-ID, hence incomplete.

Just in example, the tcp three-way-handshake could complete but then all the following packets are just TCP keepalives or something.

Packet captures will provide the answers you seek 🙂

[DominickHernandez]

I'm having this same issue with telnet on port 8080. From one server to the other it will connect for a second and then say the remote host closed the connection. 

Any ideas?

Rule 

Packet Capture

 WireShark