Sun Microsystems 2.1 manual To copy to or extract from a tape device, use smctar

■The machine on which your content is stored does not have ftp client software.

■For video file transfers from the server to a client machine, if your video file is smaller or equal to 2.1 GB, use smc_copy or ftp. If the file is larger than 2.1 GB, use smc_tar.

■For video file transfers between Sun MediaCenter servers, use Cmtool or smc_copy.

■If you want to perform a “third-party” transfer, in which you invoke a command on one machine to transfer video files between a second and a third machine, use smc_copy.

■To copy to or extract from a tape device, use smc_tar.

■Both ftp and smc_tar are useful for backup and restore of video files.

If any of these circumstances applies to you, you must create a content package as described in Appendix B, then use smc_tar to load your content. See Chapter 5 for a description of smc_tar.

When you copy content to a Sun MediaCenter server (which includes the narrower case of content loading), you, the copier, have certain access to that title that is not available to other users. You use the smc_settacl utility to change access to the copied title. See Section 5.1 “Setting a Title Access Control List” on page 5-1 an explanation of setting permissions for copied titles.

A couple of points on content loading:

■A Sun MediaCenter server can play streams while you are loading content.

■You can begin to play a title seconds after you have started loading it onto the server. This feature is called “playthrough” and is discussed in detail in the Sun MediaCenter Server Programmer’s Guide.

■For video formatted as MPEG-2 Transport Streams, Sun MediaCenter software automatically generates index files for titles that contain trick play streams.

When storing content, free space in the UFS /var partition might be a consideration. While the bulk of content storage is handled by the disk subsystem controlled by the MFS, the MFS software uses space in /var for keeping track of MFS files.

Specifically, the MFS uses:

■a small amount of space for TOC and index files (these are described in Appendix B);

■a fixed amount, 1500 bytes, for each MFS file;

■one byte for every 10 minutes of play time in a title.

The last requirement is a function of play time, not encoding rate or MFS file length.

As examples of MFS space consumption in /var, consider that a two-hour MPEG-1 title consumes 73.5 KB; a 30-second title consumes 1800 bytes. Our testing has shown free space of 10 MB on a Sun MediaCenter UltraSPARC to be adequate for a set of titles that places an extremely high demand on /var space.

2-6Sun MediaCenter Server Administrator’s Guide • December 1997