Interpreting bytes telemetry in Log99 of fortiproxy

[amoureux]

Hi guys,

I need some assistance in clarifying some of the information I'm seeing in log 99 from my fortiproxy, particularly the rcvdbytes and sentbytes.

Question 1: Does the received bytes refer to the amount of bytes received by the fortiproxy from user or vice versa?

Question 2: Does the sent bytes refer to the amount of bytes sent by user to the dest or vice versa?

Question 3: Does the HTTP method or any other telemetry within the rawlogs that may affect the order of how we see the bytes?

This is crucial because it allows me to understand if there are potential malicious exfiltration happening in my environment.

Thanks!

[dingjerry_FTNT · Accepted solution]

Thank you, @amoureux .

1) rcvdbyte is the bytes received for the initiator.

2) sentbyte is the bytes sent by the initiator.

3) I don't think so.

[dingjerry_FTNT · Accepted solution]

Keep it in mind: 

The log is for the initiator/responder, not for FortiProxy itself.

[dingjerry_FTNT]

Hi @amoureux ,

Can you explain, or attach a screenshot of what log 99 is?

[amoureux]

Hi, 

Thanks for the reply.

I'm referring to this - 99 - LOG_ID_TRAFFIC_HTTP_TRANSACTION | FortiProxy 7.6.0 | Fortinet Document Library

[dingjerry_FTNT · Accepted solution]

Thank you, @amoureux .

1) rcvdbyte is the bytes received for the initiator.

2) sentbyte is the bytes sent by the initiator.

3) I don't think so.

[dingjerry_FTNT · Accepted solution]

Keep it in mind: 

The log is for the initiator/responder, not for FortiProxy itself.

[amoureux]

thanks a lot for the information. by any chance, is there a link/documentation to better clarify this? based on the ID99 documentation, i believe it only says received bytes without the relativity. i think the relativity from whether it is for fortiproxy itself or the initiator/responder is quite important esp for security monitoring purposes.  

[dingjerry_FTNT · Accepted solution]

Unfortunately, there is no such a doc for it. You may open a technical ticket to ask for a tech doc for it.

[amoureux]

Can I ask how do I raise a technical ticket for this? Thanks in advance. 

[dingjerry_FTNT]

Hi @amoureux ,

1) You need to register an account on https://support.fortinet.com/

2) You need to register this device in this account;

3) You need to apply a valid support contract to the device.

Then please follow the instructions in this doc to create a ticket:

https://community.fortinet.com/tpykb84852/attachments/tpykb84852/TKB36/26/90/3.01%20Ticket%20Creatio...