gfsched(1) [debian man page]
GFSCHED(1) GFSCHED(1) NAME
gfsched - schedule and display available file system nodes SYNOPSIS
gfsched -f gfarm-URL [ -D domain-name ] [ -n number ] [ -LMclw ] gfsched [ -P gfarm-URL ] [ -D domain-name ] [ -n number ] [ -LMlw ] DESCRIPTION
The gfsched command with the -f gfarm-URL option displays available file system nodes which have a file replica of the specified gfarm-URL. When the -f gfarm-URL option is not specified, the gfsched command just displays available file system nodes. In this case, you can spec- ify a metadata server by the -P gfarm-URL option, if necessary. OPTIONS
-D domain-name Limits file system node by specifying a domain name or a hostname. -c Displays scheduling information for a file creation, if the file specified by -f doesn't exist. Currently, this option creates the specified file. But please note that this behavior may be changed in future. -L Suppresses authentication check. Without this option, the scheduler checks whether the user will be successfully authenticated with the hosts or not. This option omits the check to make scheduling faster, but that creates a risk that hosts which fail authentica- tion with the user may be scheduled. -M Suppresses client-side scheduling and only performs metadata-server-side scheduling. This option makes scheduling faster, but also creates a risk that hosts which is network-unreachable or fails authentication with the user may be scheduled. -P gfarm-URL Specifies a gfarm-URL or a pathname to identify a metadata server which is used for the scheduling. This option conflicts with the -f option. -f gfarm-URL The gfsched command schedules file system nodes which have a replica of a file specified by this option. This option conflicts with the -P option. -l Long format. This option displays port numbers as well as hostnames. Note that the display format of this option may be changed in future. -n number Displays specified number of file system nodes at most. If this option is not specified, it displays all available nodes. -w Schedules with write-mode. When this option is specified, file system nodes which don't have enough free space won't be displayed. When both this option and the -f are specified, and if the file is already opened by an existing process with write-mode, the gfsched command only displays one file system node which is assigned for writing to the file. -? Displays a list of command options. EXAMPLES
The following is an example to inquire file system nodes that the metadata server thinks they are currently working. $ gfsched -M Gfarm 28 December 2010 GFSCHED(1)
Check Out this Related Man Page
GFS_PIO_OPEN(3) GFS_PIO_OPEN(3) NAME
gfs_pio_open - open a file in the Gfarm file system SYNOPSIS
#include <gfarm/gfarm.h> gfarm_error_t gfs_pio_open (const char * gfarm_url, int flags, GFS_File * gfp); DESCRIPTION
gfs_pio_open() opens a file in the Gfarm file system specified by gfarm_url, and returns a GFS_File structure to the address pointed by gfp. gfarm_url is a path name in the Gfarm file system, or a Gfarm URL in the form of gfarm://metaserver:port/path/name. Values of flags are constructed by a bitwise-inclusive-OR of the following list. Exactly one of the first three values should be speci- fied: GFARM_FILE_RDONLY Open for reading only. GFARM_FILE_WRONLY Open for writing only. GFARM_FILE_RDWR Open for reading and writing. GFARM_FILE_TRUNC If the file already exist and is a regular file, it will be truncated to length 0 if the open mode allows writing. RETURN VALUES
GFARM_ERR_NO_ERROR The function terminated successfully. GFARM_ERR_IS_A_DIRECTORY gfarm_url refers to a directory. GFARM_ERR_IS_A_SYMBOLIC_LINK gfarm_url refers to a symbolic link. GFARM_ERR_OPERATION_NOT_PERMITTED gfarm_url refers to not a regular file. GFARM_ERR_NO_SUCH_OBJECT A component used as a directory in gfarm_url does not exist. GFARM_ERR_NOT_A_DIRECTORY A component used as a directory in gfarm_url is not, in fact, a directory. GFARM_ERR_PERMISSION_DENIED The requested access to the file is not allowed, or one of the directories in gfarm_url did not allow search (execute) permission. Or, the authentication to the metadata server fails. GFARM_ERR_NO_MEMORY Insufficient memory was available. GFARM_ERR_INVALID_ARGUMENT flags is not valid. GFARM_ERR_GFARM_URL_HOST_IS_MISSING gfarm_url does not include a metadata server. GFARM_ERR_GFARM_URL_PORT_IS_MISSING gfarm_url does not include a port number of the metadata server. GFARM_ERR_UNKNOWN_HOST The metadata server cannot be resolved. GFARM_ERR_TOO_MANY_OPEN_FILES The process opens too many files. GFARM_ERR_TOO_MANY_OPEN_FILES_IN_SYSTEM The system limit on the total number of open files has been reached. GFARM_ERR_NETWORK_IS_UNREACHABLE Network is unrechable. GFARM_ERR_OPERATION_TIMED_OUT Connetion timeout occurs. GFARM_ERR_PROTOCOL Protocol error occurs. GFARM_ERR_BROKEN_PIPE Connection to the metadata server is broken. GFARM_ERR_PROTOCOL_NOT_SUPPORTED Specified authentication protocol is not supported. GFARM_ERR_AUTHENTICATION User authentication failed when connecting to the metadata server. Others An error except the above occurred. The reason is shown by gfarm_error_string(3). SEE ALSO
gfs_pio_close(3), gfs_pio_create(3), gfs_pio_eof(3), gfs_pio_error(3), gfs_pio_flush(3), gfs_pio_getc(3), gfs_pio_getline(3), gfs_pio_open(3), gfs_pio_putc(3), gfs_pio_putline(3), gfs_pio_puts(3), gfs_pio_read(3), gfs_pio_seek(3), gfs_pio_ungetc(3), gfs_pio_write(3) Gfarm 27 June 2010 GFS_PIO_OPEN(3)