Multitasking - Not All Clients Start Tasking

[Joe Gill]

FOG Server Ver. - 1.5.4
FOG OS - Debian 9.4
HOST OS - WIN10

I have noticed on multiple occasions that in some of my labs the multicast sessions only complete on a select group of hosts and do not start on others.

What happens is:
ALL hosts in Group WOL
ALL hosts get to the PARTCLONE screen.
Partial hosts start tasking and complete tasking.

I noticed this in one lab where one host would start PARTCLONE tasking and all other hosts would not start. I had to unplug that host from the network in order to get the others to actually finish tasking.

In every situation, previous versions of FOG worked correctly Multicasting to these labs.

@george1421 - Any ideas on what might be going on here? Everything else has been stable since we talked last.

Thanks!

Cheers,

Joe

[Joe Gill]

I just checked over my Multicast settings int FOG settings…

UDPCAST Maxwait is set to 10.

[Joe Gill]

Also this particular session started with 36 clients.

[Tom Elliott]

@joe-gill try setting the fog setti mg for multicast rendezvous to the up of the fog server you are expecting the data to be sent from. This isn’t a typical case for use of this but it has had to be used in a few environments.

[Joe Gill]

@tom-elliott

@george1421 had me set the Multicast rendezvous address to our FOG server IP previously.

Thanks!

[george1421]

@joe-gill said in Multitasking - Not All Clients Start Tasking:

had me set the Multicast rendezvous address to our FOG server IP previously

Nope not me, that bit of hocus-pocus sounds something like what Tom would say.

Is your fog server and multicasting clients on the same subnet?

[Joe Gill]

@george1421

Well it may have been Tom. But I thought you told me that. Ha!

Our machines are all on the same subnet.

[Tom Elliott]

Are you on the working branch? Can you show us the /var/log/fog/multicast.log file?

[Joe Gill]

@tom-elliott
Yes I am on the working branch. I’ll post the log file here shortly.

[Joe Gill]

@Tom-Elliott

The last line repeats until it finished.

If you would like the entire log file I can post it.

[Tom Elliott]

@joe-gill So you’re saying some machines work fine, not all of them though?

[Tom Elliott]

Sorry for reasking the questions you’ve already answered, just trying to understand the whole situation.

[Tom Elliott]

I’m assuming, for the log you posted, there were only 27 hosts in that group that needed the tasking?

[Joe Gill]

@tom-elliott

That is correct.

Some machines start multitasking like normal and others sit on the Partclone screen. All of them make it to the Partclone screen at the same time.

[Tom Elliott]

So chatting with @Joe-Gill We narrowed down what the problem.

First, the backstory.

So Multicast tasks would work for some machines, but not all. And, to add to that, it was always the same machines that failed to work. If the machines that failed were subsequently put into their own group, they would multicast without issue.

This lead me to ask if the machines that would fail were on a different switch from the rest of the machines, and indeed @Joe-Gill found out that this was the case. They are using Meraki switches and they replaced a few of them. Those that were replaced do not work fluidly with the older switches in place.

@Joe-Gill keep me truthful here, but this is the gist of this information.

[george1421]

@tom-elliott Also be aware in another thread we had to make some changes to the www.conf file (adding the memory limit of 256MB). He also had 3 versions of php and php-fpm installed. When I left the session (a few days ago) he had no more than 6 active php-fpm worker threads for 24 hosts in a multicast. Memory and CPU usage looked good, but understand I was only focused on why php-fpm was behaving so badly on his system.

@Joe-Gill Check to see if igmp snooping is turned on, for your network switches. That will allow the switches to handle multicast traffic a bit more intelligently.

[Joe Gill]

@tom-elliott

That is excactly correct. I am reaching out to our vendor to find out if their are any known issues here. I will post back for others to know.

For the record we are using Meraki MS225-48FP and Meraki MS42P.

Thanks for helping be troubleshoot this @Tom-Elliott .

[Joe Gill]

@george1421 Thanks! I’ll check it out.

[Joe Gill]

@george1421
IGMP snooping is enabled.

[george1421]

@joe-gill said in Multitasking - Not All Clients Start Tasking:

@george1421
IGMP snooping is enabled.

For all switches (even meraki), on the vlan where the machines are multicasting?