GFHOST(1)

💖 GFHOST(1) — Gfarm filesystem node management command 💖

okay bestie, pull up a chair 🪑 because this is the page for managing filesystem nodes in Gfarm, straight out of the Gfarm manual. yes the manual is literally named Gfarm, that's the brand, we love that for it 💅

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✨ NAME ✨

gfhost — Gfarm filesystem node management command

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🌸 SYNOPSIS 🌸

gfhost [-H | -l | -M] [-iLprUv] [-P path] [-a architecture]
       [-D domain-name] [-j concurrency] [hostname...]

gfhost -c [-P path] -a architecture -p port-number [-n number-of-CPUs]
       [-f flags] hostname

gfhost -m [-P path] [-a architecture] [-p port-number]
       [-n number-of-CPUs] [-f flags] hostname

gfhost -d [-P path] hostname...

gfhost -R [-P path]

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🦋 DESCRIPTION 🦋

gfhost is the girl who displays the information of filesystem nodes. she also registers a new filesystem node, and modifies and deletes the registered information. multi-talented, no cap ✨

the way that gfhost behaves is decided by the option you pick: -c, -m, -d, -H, -l, -M, and -R. these functions are mutually exclusive — only ONE of them can be specified, pick a lane babe 🚫. if you don't specify any of them, filesystem nodes will be listed, which is the default function of gfhost. so if you're lazy, you still get output. iconic.

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👑 FUNCTIONS 👑

the Gfarm filesystem manages filesystem nodes at the gfmd metadata server. here's the tea:

• the -c option registers a new filesystem node 🆕
• the -m option modifies the registered information ✏️
• the -d option removes an entry of the filesystem node and related file metadata 🗑️
• the -R option restores the dumped information of filesystem nodes, which is obtained by the -M option ♻️

these operations require gfarmadm privilege. you need the badge, bestie, no sneaking in 🙈

when -H, -l, -M, or no functional option is specified, gfhost displays filesystem node information. the -M lists the registered information of filesystem nodes at the gfmd metadata server. other options access gfsd filesystem daemon to obtain more information and also to check the accessibility to a filesystem node. the -i, -j, -U and -v options are available.

when hostnames of filesystem nodes are not specified, all registered hosts will be displayed, but you can limit the type of hosts displayed by the -a and/or -D option. by default, hosts are displayed in alphabetical order, but you can change this by the -L, -p, or -r option, although the -L option is effective with -H or -l option.

the following is a list of the functions of the gfhost command. you shouldn't specify more than one function at a time. one function. one. that's the rule 🫶

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🌈 the functions, one by one 🌈

• <none> — when no function is specified, gfhost accesses to gfsd, and displays the host names which are currently available. they are displayed in alphabetical order, by default. the chill default mode 😌
• -c — creates a host entry of a filesystem node that is specified by the argument. the -a option is mandatory, which specifies the architecture of the filesystem node. the -p option is mandatory, which specifies the port number of gfsd on the filesystem node. the -n option is optional, which specifies the number of CPUs of the filesystem node. when it is omitted, 1 CPU is assumed. the -f option is optional, which specifies the flag of the file system node. when it is omitted, 0 is assumed.
• -d — deletes a host entry. all file metadata is also asynchronously updated to delete invalid replica entries for the removed filesystem node, and to create file replicas if required, automatically. she cleans up after herself, we stan a tidy queen 🧹
• -l — displays in a long format, which consists of the CPU load average, authentication method, architecture, the number of CPUs, hostname, port number, flags, and the IP address. the full glow-up report 💅

if the host cannot be accessed due to a machine down or a network problem, etc., x.xx/x.xx/x.xx will be displayed in the CPU load average field. if the host is up, but gfsd on the host cannot be accessed, -.--/-.--/-.-- will be displayed.

in the field of the authentication method, G means the GSI authentication and the encryption, g means only authentication is performed by GSI and actual communication is unprotected plain data (gsi_auth), s means the gfarm sharedsecret authentication, x means that the authentication fails, and - means that the authentication wasn't actually tried. with the -U option, there is no authentication method field.

in the field of the flags, refer to the -f option.

hostnames are displayed in alphabetical order, by default.

• -H — displays filesystem nodes with the CPU load average and the authentication method. this function also displays the IP address used to access to gfsd in parentheses just after the hostname. like a little name tag 🏷️

for the field of the CPU load average and the authentication method, refer to the -l option.

hostnames are displayed in alphabetical order, by default.

• -M — dumps the metadata information of the registered filesystem nodes. hostnames are displayed in alphabetical order, by default.
• -m — modifies the registered metadata information of the filesystem node. the -a, -p, -n, and/or -f option modify the current value of each option. glow-up edit pass ✨
• -R — restores the metadata information read from standard input. the format of the metadata is same as the format that the -M function displays. so -M then -R, a little round trip, we love a system that talks to itself 💞
• -? — prints usage. the "help me" button, we've all been there 😭

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💅 OPTIONS 💅

• -a architecture — this option specifies the CPU architecture using a format like sparc-sun-solaris8 or i386-redhat8.0-linux, etc. if this option is used with the -c or -m function, this means the architecture used to add/modify the metadata information. if this option is used with -H, -l, -M function or default function, this limits hosts to the specified architecture.
• -D domain-name — this option is used with the -H, -l, -M function or the default function to limit hosts to the specified domain. filtering, but make it fashion 🎀
• -i — there is an "address_use" directive in %%SYSCONFDIR%%/gfarm2.conf and $HOME/.gfarm2rc to give priorities of network addresses for gfarm access. this directive works with the gfhost command, but will be ignored, if you specified the -i option with gfhost. she said not today 🚫
• -j concurrency — this option specifies the concurrency used for access to gfsd. the default value is 10.
• -L — sorts by load average order. this option is effective only with the -H and -l functions .
• -n number-of-CPUs — this option is used with the -c or -m function, and specifies the number of CPUs of the host.
• -p port-number — this option is used with -c or -m function, and specifies the port number of gfsd on the host.
• -f flags — this option is used with -c or -m function, and specifies the flags of gfsd on the host. values of flags are constructed by a bitwise-or of the following list.
  • 1 — readonly
• -P path — this option specifies a pathname or a Gfarm URL to identify a metadata server which will be accessed by this command. if not specified, "/" is used as the default value.
• -r — reverses the order of sort. flip it, reverse it 📱
• -u — plain order. this option stops sorting on the -H, -l, -M function or the default function. with the -M function, command argument order (if any), or the order that the metadata server answers is used for display. with the -H, -l function or the default function, the result is displayed in the order that each gfsd answers. no sorting, just vibes 🌸
• -U — suppresses authentication attempts by TCP, and only queries load average by UDP. this option only makes sense if you specified the -H or -l function, or if you didn't specify any function. this option makes the gfhost command run faster ⚡. if the -H or -l function is specified, this option makes the authentication method field disappear.
• -v — the -H, -l function and the default function don't produce error reports on gfsd accesses; these error reports will be produced by this option. she's quiet until you ask her to spill 🗣️

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🫶 SEE ALSO 🫶

• gfarm2.conf(5)
• gfsd(8)

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and that's the whole page, bestie, you ate that 💖

this little love letter to filesystem nodes came from the Gfarm manual, dated 14 Mar 2019, and it lives at section GFHOST(1). go forth and manage those nodes, main character 👑✨