Difference between revisions of "Mythbackend"
(Added information on -v switch) |
(→Interpreting --printsched Output: Remove outdated recording type character list/descriptions and link to pages showing those characters.) |
||
| (18 intermediate revisions by 11 users not shown) | |||
| Line 1: | Line 1: | ||
| − | The backend process (mythbackend) is the portion of the system that handles the [[Video capture card]]s as well as [[Scheduling Recordings]] on those cards, [[Commercial | + | The backend process (mythbackend) is the portion of the system that handles the [[Video capture card]]s as well as [[Scheduling Recordings]] on those cards, [[Commercial Detection]], and [[transcoding]]. The backend process interacts with the [[Database]] primarily. |
| − | As with the [[ | + | As with the [[mythfrontend]], there can be multiple backends. One backend process is designated as the master backend. This is usually the first backend installed on a system. This backend is responsible for coordinating the activities of the other backends known as slaves. This is especially true for scheduling as the master backend will determine the best distribution of programs across all available tuners. Each backend can have any number of tuners. A machine that does not have any tuners attached can store and serve content by running [[mythmediaserver]] instead of mythbackend. [[Commercial Detection]] can be distributed across multiple backends, and other machines running [[mythjobqueue]], thereby spreading the load of that process. |
There is no requirement for direct user interaction with the backend. The backend can use local [[HardWare]]/[[File Storage]] or have it mounted from another system. If remotely mounted, network performance should be considered as there will be considerable traffic on the network as recordings are stored and retreived by the backend process. | There is no requirement for direct user interaction with the backend. The backend can use local [[HardWare]]/[[File Storage]] or have it mounted from another system. If remotely mounted, network performance should be considered as there will be considerable traffic on the network as recordings are stored and retreived by the backend process. | ||
| + | |||
| + | == Command Line Options == | ||
| + | To get an accurate list of options for the installed version of mythbackend, | ||
| + | type: | ||
| + | <pre> | ||
| + | mythbackend --help | ||
| + | </pre> | ||
| + | In modern versions, typing ''mythbackend --help <option_name>'' also works | ||
| + | and may provide more information on the option selected. | ||
== Communications Protocol == | == Communications Protocol == | ||
| − | The | + | The [[mythbackend]] and [[mythfrontend]] communicate using their own [[:Category:Myth Protocol|Myth Protocol]]. Work on defining the [[:Category:Myth Protocol|Myth Protocol]] is being performed on this Wiki. |
== Troubleshooting == | == Troubleshooting == | ||
| − | + | Mythbackend uses the [[Logging|logging routines]] shared by the rest of MythTV, and the command line options defined there can be used to control where and what debugging information is logged. | |
| − | + | ''Need to add backend-specific troubleshooting help here, or at least link to [[Troubleshooting]]'' | |
| − | |||
| − | + | == Interpreting --printsched Output == | |
| − | + | The --printsched command line option prints out upcoming scheduled recordings. | |
| − | |||
| − | |||
| − | |||
| − | |||
| − | |||
| − | |||
| − | |||
| − | |||
| − | |||
| − | |||
| − | |||
| − | |||
| − | |||
| − | |||
| − | |||
| − | |||
| − | |||
| − | |||
| − | |||
| − | |||
| − | |||
| − | |||
| − | |||
| − | + | This format is also used in mythbackend logs of scheduling activity (with <tt>-v schedule</tt>), and is particularly useful when obtaining schedule data with <tt>--testsched</tt>. | |
| − | + | For example: | |
| − | + | <pre> | |
| − | + | Title - Subtitle Ch Station Day Start End S C I T N Pri | |
| − | + | Ask This Old House - "Installi 21_2 WLIWDT2 13 16:30-17:00 1 1 1 A 1 0 | |
| − | + | The Simpsons - "Treehouse of Horro 11 WPIX 13 19:00-19:30 1 0 0 A R 0 | |
| + | </pre> | ||
| − | The | + | Title, subtitle, channel (number), station (callsign), day, start (time) and end (time) are rather straight forward. The meanings of the other columns are: |
| − | + | * S - Source ID | |
| − | + | * C - Card ID | |
| − | + | * I - Input ID | |
| − | + | * T - [[Recording_Type_Character|Recording Type Character]] | |
| − | + | * N - [[Recording_Status_Character|Recording Status Character]] | |
| − | + | * Pri - Priority | |
| − | [[Category: | + | [[Category:MythTV_Software]] |
[[Category:Glossary]] | [[Category:Glossary]] | ||
Latest revision as of 15:27, 19 September 2016
The backend process (mythbackend) is the portion of the system that handles the Video capture cards as well as Scheduling Recordings on those cards, Commercial Detection, and transcoding. The backend process interacts with the Database primarily.
As with the mythfrontend, there can be multiple backends. One backend process is designated as the master backend. This is usually the first backend installed on a system. This backend is responsible for coordinating the activities of the other backends known as slaves. This is especially true for scheduling as the master backend will determine the best distribution of programs across all available tuners. Each backend can have any number of tuners. A machine that does not have any tuners attached can store and serve content by running mythmediaserver instead of mythbackend. Commercial Detection can be distributed across multiple backends, and other machines running mythjobqueue, thereby spreading the load of that process.
There is no requirement for direct user interaction with the backend. The backend can use local HardWare/File Storage or have it mounted from another system. If remotely mounted, network performance should be considered as there will be considerable traffic on the network as recordings are stored and retreived by the backend process.
Contents
Command Line Options
To get an accurate list of options for the installed version of mythbackend, type:
mythbackend --help
In modern versions, typing mythbackend --help <option_name> also works and may provide more information on the option selected.
Communications Protocol
The mythbackend and mythfrontend communicate using their own Myth Protocol. Work on defining the Myth Protocol is being performed on this Wiki.
Troubleshooting
Mythbackend uses the logging routines shared by the rest of MythTV, and the command line options defined there can be used to control where and what debugging information is logged.
Need to add backend-specific troubleshooting help here, or at least link to Troubleshooting
Interpreting --printsched Output
The --printsched command line option prints out upcoming scheduled recordings.
This format is also used in mythbackend logs of scheduling activity (with -v schedule), and is particularly useful when obtaining schedule data with --testsched.
For example:
Title - Subtitle Ch Station Day Start End S C I T N Pri Ask This Old House - "Installi 21_2 WLIWDT2 13 16:30-17:00 1 1 1 A 1 0 The Simpsons - "Treehouse of Horro 11 WPIX 13 19:00-19:30 1 0 0 A R 0
Title, subtitle, channel (number), station (callsign), day, start (time) and end (time) are rather straight forward. The meanings of the other columns are:
- S - Source ID
- C - Card ID
- I - Input ID
- T - Recording Type Character
- N - Recording Status Character
- Pri - Priority
