Error - Network Clock is not Locked - Video Satellite

[Naught1]

Running Video Satellite LE, we recently started seeing more and more "Cannot start Playback. Network Clock is not Locked" errors. In a 90-minute playback this error popped 5 times. Clicking the OK button allowed playback to resume. Naturally this happened during a screening with the Director.

We've been running Video Satellite LE happily for about a year, and this problem only came up once or twice per week.

Per previous threads, I've verified that all three systems are running the same sample rate and timecode settings.

The LE and 2 HD rigs are running 8.01cs1 instead of 8.03 due to 3rd party software limitations (Virtual Katy).

Since this points to a network issue, I should point out that the 3 systems connect to the same local gigabit switch, which then goes to a master gigabit switch, then on to the router/firewall.

So here are my questions:

1. Could this stacked switching be the source of the problem? We haven't previously noted problems with speed over this connection, but it's possible that certain types of traffic may be limited by it.

2. Or does the local switch handle the traffic between the systems?

3. Since the MacPros these run on (all identical 2x2.66 dual cores) have 2 ethernet ports, can one of them be dedicated to run the VS traffic? That is, can I simply connect all 3 to the same dedicated gigabit switch (which would do nothing else) and somehow get the VS networking to use only the dedicated ethernet ports?

Thanks for the responses!

[Postman]

I've seen that very rarely here, and both PT and Mac are plugged into the same Gbit switch, which is plugged into another Gbit switch. What's different for me is, when the message pops up, it is usually first thing in the morning when first launching apps. I simply reboot both computers (MC and PT) and the problem is gone. It might have popped up once during a gig. I don't think I've seen it for months.

I'm not being very helpful, but if it's come up more frequently for you, something MUST have changed. Maybe an OS update?

[Bob Brown]

Hi Naught1,

The network clock is not locked error seems to imply there are some issues with your network that are causing high latencies for the communication between the Pro Tools rigs.

One thing you should noticed when you get this error is the middle dots on the "link" button will be flashing when the network clock is not locked.

It should also be noted that opening a session, resetting things in the Playback Engine Dialog, among a few other things will cause a reset of the network clock. Typically, the network clock should relock within 1 to 3 seconds. If you immediately open a session, link and press play, you might get the error.

You should not be seeing the error come up randomly when you are working and playing back in Pro Tools.

Do you know what the traffic is on the switch your Pro Tools systems are connected to? For example, are you copying lots of data off of shared storage, using other ethernet hungry pieces of software, or something similar that could be slowing down the network traffic?

Thanks

[Naught1]

Yes Postman, there was a change a few months back- the VS rig was downgraded to match the others in the system via clean install. OS and PT versions remained the same. I had to increase the hardware buffer by one step on the downgraded rig to avoid processor overruns caused by the Avid DNxHD codec, but other than that, the setup is the same for software.

Network traffic has increased in general over the last year, just not on the gear connected to the local switch. The network configuration isn't perfect, in that it would be better not to stack the switches. That's why I'm looking to isolate the VS traffic on a dedicated network.

One other possible fix might be to run 3 dedicated lines from the HD and VS rigs to the main switch. That's a 300 foot run, which might add its own latency to the connection, and defeat the purpose. Is that going to help?

[Bob Brown]

Is it possible to put the 3 rigs on a switch that is not connected to the rest of your network to see if that makes the problem go away?

I my development and testing work, I typically have "stacked" switches. I haven't seen the types of problems you are experiencing.

What is the model of switch that you are connecting the Pro Tools rigs to?

Is it a gigabit or 100baseT or 10baseT?

[Naught1]

Thanks, Bob. The local switch is a Linsksys SR2016, it's 10BASE-T/100BASE-TX/1000BASE-TX and auto negotiates.

I would fully isolate the rigs, but we're in production now, and require fast connection to servers. Later on I can isolate that way, though.