17-7
UserGuide for Cisco Digital Media Manager5.4.x
OL-15762-05
Chapter17 Media Assets and Embedde d Software
Concepts
Understand HTTP ‘HEAD’ Request Timeout
Before it tries to download content from a webserver, your DMP first makes sure that the content exists
at its expected address. Your DMP starts this validation by sending the webserver what’s called an HTTP
HEAD request. Then, when the webserver responds within a configurable interval (10 seconds , by
default) to verify that the expected address is valid, your DMP sends an HTTP GET request that triggers
the actual download.
Note This configurable interval is based on the “Failover Timeout (ms)” value in DMPDM. Therefore, this value has a powerful
effect on your digital signs even when content failover is disabled. It is the maximum duration that can elapse before your DMP
sends an HTTP GET request.
•
Timeout Benefit, page17-7
•
Timeout Risk, page 17-7
•
You Can Configure the Timeout on Centrally Managed DMPs, page17-7
•
You Can Configure the Timeout on One DMP in Isolation, page17-8
•
You Can Disable the Timeout on Centrally Managed DMPs, page17-9
•
You Can Disable the Timeout on One DMP in Isolation, page17-10
Timeout Benefit
When the webserver takes more than the configured interval to respond
OR
when its response is negative,
your DMP enters a content substitution (“failover”) state. In this state, your DMP substitutes available
assets for unavailable ones. So, instead of showing a black screen, this behavior causes an affected digital
sign to play alternative content that you chose previously. The underlying logic for this behavior
anticipates a serious problem and overcomes it gracefully.
Timeout Risk
However, this logic cannot account for all possible scenarios. When a webserver would otherwise verify
that an asset’s address is valid, your DMP misinterprets the delay and enters its content failover state
unnecessarily.
You Can Configure the Timeout on Centrally Managed DMPs
You can use DMM to edit this timeout.
1.
Click Network and Endpoints.
2.
Choose Digital Media Players > Advanced Tasks > System Tasks.