| 1 | There are two strategies the File Server can use for attaching AFS volumes |
| 2 | at startup and handling volume salvages. The traditional method assumes |
| 3 | all volumes are salvaged before the File Server starts and attaches all |
| 4 | volumes at start before serving files. The newer demand-attach method |
| 5 | attaches volumes only on demand, salvaging them at that time as needed, |
| 6 | and detaches volumes that are not in use. A demand-attach File Server can |
| 7 | also save state to disk for faster restarts. The B<dafileserver> implements |
| 8 | the demand-attach method, while B<fileserver> uses the traditional method. |
| 9 | |
| 10 | The choice of traditional or demand-attach File Server changes the |
| 11 | required setup in F<BosConfig>. When changing from a traditional File |
| 12 | Server to demand-attach or vice versa, you will need to stop and remove |
| 13 | the C<fs> or C<dafs> node in F<BosConfig> and create a new node of the |
| 14 | appropriate type. See L<bos_create(8)> for more information. |
| 15 | |
| 16 | Do not use the B<-w> argument, which is intended for use |
| 17 | by the OpenAFS developers only. Changing it from its default |
| 18 | values can result in unpredictable File Server behavior. |
| 19 | |
| 20 | Do not specify both the B<-spare> and B<-pctspare> arguments. Doing so |
| 21 | causes the File Server to exit, leaving an error message in the |
| 22 | F</usr/afs/logs/FileLog> file. |
| 23 | |
| 24 | Options that are available only on some system types, such as the B<-m> |
| 25 | and B<-lock> options, appear in the output generated by the B<-help> |
| 26 | option only on the relevant system type. |
| 27 | |
| 28 | Currently, the maximum size of a volume quota is 2 terabytes (2^41 bytes) |
| 29 | and the maximum size of a /vicepX partition on a fileserver is 2^64 |
| 30 | kilobytes. The maximum partition size in releases 1.4.7 and earlier is |
| 31 | 2 terabytes (2^31 bytes). The maximum partition size for 1.5.x |
| 32 | releases 1.5.34 and earlier is 2 terabytes as well. |
| 33 | |
| 34 | The maximum number of directory entries is 64,000 if all of the entries |
| 35 | have names that are 15 octets or less in length. A name that is 15 octets |
| 36 | long requires the use of only one block in the directory. Additional |
| 37 | sequential blocks are required to store entries with names that are longer |
| 38 | than 15 octets. Each additional block provides an additional length of 32 |
| 39 | octets for the name of the entry. Note that if file names use an encoding |
| 40 | like UTF-8, a single character may be encoded into multiple octets. |
| 41 | |
| 42 | In real world use, the maximum number of objects in an AFS directory |
| 43 | is usually between 16,000 and 25,000, depending on the average name |
| 44 | length. |