diff options
Diffstat (limited to 'Documentation/filesystems')
| -rw-r--r-- | Documentation/filesystems/pohmelfs/design_notes.txt | 5 | ||||
| -rw-r--r-- | Documentation/filesystems/pohmelfs/info.txt | 21 |
2 files changed, 20 insertions, 6 deletions
diff --git a/Documentation/filesystems/pohmelfs/design_notes.txt b/Documentation/filesystems/pohmelfs/design_notes.txt index 6d6db60d567..dcf83358716 100644 --- a/Documentation/filesystems/pohmelfs/design_notes.txt +++ b/Documentation/filesystems/pohmelfs/design_notes.txt @@ -56,9 +56,10 @@ workloads and can fully utilize the bandwidth to the servers when doing bulk data transfers. POHMELFS clients operate with a working set of servers and are capable of balancing read-only -operations (like lookups or directory listings) between them. +operations (like lookups or directory listings) between them according to IO priorities. Administrators can add or remove servers from the set at run-time via special commands (described -in Documentation/pohmelfs/info.txt file). Writes are replicated to all servers. +in Documentation/pohmelfs/info.txt file). Writes are replicated to all servers, which are connected +with write permission turned on. IO priority and permissions can be changed in run-time. POHMELFS is capable of full data channel encryption and/or strong crypto hashing. One can select any kernel supported cipher, encryption mode, hash type and operation mode diff --git a/Documentation/filesystems/pohmelfs/info.txt b/Documentation/filesystems/pohmelfs/info.txt index 4e3d5015708..db2e4139362 100644 --- a/Documentation/filesystems/pohmelfs/info.txt +++ b/Documentation/filesystems/pohmelfs/info.txt @@ -1,6 +1,8 @@ POHMELFS usage information. -Mount options: +Mount options. +All but index, number of crypto threads and maximum IO size can changed via remount. + idx=%u Each mountpoint is associated with a special index via this option. Administrator can add or remove servers from the given index, so all mounts, @@ -52,16 +54,27 @@ mcache_timeout=%u Usage examples. -Add (or remove if it already exists) server server1.net:1025 into the working set with index $idx +Add server server1.net:1025 into the working set with index $idx with appropriate hash algorithm and key file and cipher algorithm, mode and key file: -$cfg -a server1.net -p 1025 -i $idx -K $hash_key -k $cipher_key +$cfg A add -a server1.net -p 1025 -i $idx -K $hash_key -k $cipher_key Mount filesystem with given index $idx to /mnt mountpoint. Client will connect to all servers specified in the working set via previous command: mount -t pohmel -o idx=$idx q /mnt -One can add or remove servers from working set after mounting too. +Change permissions to read-only (-I 1 option, '-I 2' - write-only, 3 - rw): +$cfg A modify -a server1.net -p 1025 -i $idx -I 1 + +Change IO priority to 123 (node with the highest priority gets read requests). +$cfg A modify -a server1.net -p 1025 -i $idx -P 123 +One can check currect status of all connections in the mountstats file: +# cat /proc/$PID/mountstats +... +device none mounted on /mnt with fstype pohmel +idx addr(:port) socket_type protocol active priority permissions +0 server1.net:1026 1 6 1 250 1 +0 server2.net:1025 1 6 1 123 3 Server installation. |