SOLVED "List hosts" page FOG does not ping Linux hosts

  • Am I right in determining that on the “List hosts” page FOG does not ping Linux hosts, because the Ping class only looks at the NetBios port? My linux hosts show up at “connection refused.”


  • Senior Developer

    @Wayne-Workman I do not know. Pinging directly may be a better option, but I would not recommend it. ICMP is not really a good mechanism to test up/down state. This is because ICMP knows nothing about the host, nor does it really care. Remember, we aren’t directly tracking the IP of a host any more, and this is for good reason in my eyes. Basically, the current mechanism knows what host is what because it translates the Hostname to its corresponding IP address. If you want to just know if a host is “pingable” then you should probably add the Host IP field back and enter the corresponding host’s IP address. This way, even if the host is currently rebooting, it will respond if the network is up and running.

  • @Tom-Elliott Is there a way to test it from CLI in linux? Sending something to a hostname on port 445? Just for troubleshooting?

  • Senior Developer

    @Uncle-Frank @Wayne-Workman @Jeff-Swicegood

    Regular ICMP is fine, but it doesn’t return error codes that can be easily used to report the real status. 1.2.0 doesn’t matter as those error codes aren’t parsed out at all, but dev uses it’s own internal string comparison to get the “real” status in a string form.

    Port 445 is an old NetBIOS and now primarly used for SMB. installing an SMB Server on a linux box should enable port 445 to operate in both directions, but in the case of linux, 445 being blocked at all for a ping is likely the problem to begin with. Disable blocking on the port should work for the scenario as well as installing samba. Because 445 is already used on windows Boxes, we cannot enable the client to “listen” on it as it’s already running.

  • Senior Developer

    Or maybe just use normal ICMP ping?

  • @Jbob what’s the chances of the new FOG Client listening on port 445 so that this feature works across the board on all OSs to get this feature to work as it should?

  • FOG 1.2 on Ubuntu 14.04. Yes pinging is allowed,but from what I can tell, FOG doesn’t “Ping” at all. It does a probe on port 445 of the hosts instead of a ping. It says in the comments in the code (Pingclass) that a real system ping would take up too much system resources. So Linux hosts with nothing running on port 445 show up as connection refused, even though they allow ping.

    I found a workaround though.

    When I installed samba on the linux host, it shows up with a green dot on the “lists hosts” page just like it should. The samba package includes the smbd deamon which listens on port 445.

  • Senior Developer

    What version of FOG? What is the OS FOG is running on? Is Pinging enabled on the FOG Server? Is pinging allowed on the Windows clients?

    Basically, we need details to better help.