During the course of your cinema’s daily operations you can easily send terabytes of content between your screens every week. In addition to the KDM errors we covered previously, there are some issues that can crop up during routine content transfers that can threaten your screenings.
To resolve these issues as quickly as possible, you should try to gather as much information about the error as possible, and try some workarounds. That’s why we created a downloadable troubleshooting checklist to print out for your projection booths.
Content transfer basics
When your cinema receives its content, whether from physical hard drives, transfers from your head office or satellite deliveries, it will go into your LMS (Library Management System). This LMS is simply a data store; it cannot play content directly. To get content onto the screen, a copy is transferred from your LMS to the individual screen servers.
The first step in troubleshooting what has caused a transfer failure is to check the transfer status of the content in your TMS. In Screenwriter for example, navigate through the Content menu to the Transfer Status tab and click on the relevant CPL (Composition Playlist) to check what error message it received. To learn more about what CPLs are, read our article on KDMs.
The most common errors occur because there isn’t enough storage space on the screen server to transfer the content. To prevent this kind of error, try to keep your screen servers clean by deleting old content and playlists, and always check that they have enough storage space before scheduling your content transfers.
If the error flags a network connection issue, you should be able to conduct a basic diagnosis through your TMS. For example, in Screenwriter, you can navigate through the Configuration menu to the Complex tab and click on the gear icon within the Screen panel to perform a simple network check. It is important to test both the management and content networks, as they are both required to perform a successful transfer.
The management network is the connection that allows your TMS to send commands to your screen server, and the content network is a separate connection used exclusively to handle the high bandwidth requirements of content transfers. This means that performing content transfers doesn’t slow down your servers’ response time, so you can continue to complete tasks with it. However, it can cause confusion because even if the server is accepting commands through your TMS, if your content network is down, the transfer will fail.
If content is transferring slowly, check that the screen server isn’t currently playing back. It is normal for transfer speeds to vary during playback, as servers will prioritise the playback over the transfers. Slow transfer times outside of playback could indicate that your screen server has a degraded RAID, and this should be reported to your hardware manager.
Occasionally the transfer error may have been triggered because the CPL has been corrupted or has an error within it. There are a variety of technical reasons why a CPL might be corrupted, ranging from a network issue causing lost packets during transfer, to faults with the hard drive that caused errors when writing the files. In these cases, there are a few steps you can take to try to end up with playable content.
First, try deleting the content completely from the LMS, and then reingesting it from the original hard drive. If that doesn’t resolve the issue, you can try to transfer the content to a different screen server. If the content works on that screen, there may be an issue with the original screen server. Sometimes, a piece of content may have been deleted from the screen server and then transferred back in. If the transfer fails, it might mean that the content wasn’t completely deleted and some junk files called ‘orphan assets’ remain on the hard drive. You can purge these orphan assets from the hard drive and then retry the transfer.
If all else fails, you can also try to ingest the content directly onto the screen server.
After completing these basic troubleshooting steps, if you still cannot transfer the content, contact your NOC with the details.
Topics: Cinema Technology