LCTL-NETWORK(8)

✨ LCTL-NETWORK 💅 (that's section 8 of the manual, bestie)

okay so this is lctl-network from the Lustre Configuration Utilities — yes it's an admin command, yes it's giving main character energy, and yes we're gonna walk through it together 🫶

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🌸 NAME 🌸

lctl-network — start or stop an LNet network, or set the network type ✨

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🎀 SYNOPSIS 🎀

lctl network {up|down} | {configure|unconfigure} | {tcp|o2ib}

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💖 DESCRIPTION 💖

okay so lctl network is your girl for starting or stopping LNet and LNet configuration on a client, a server, or a router. no cap.

and pssst — lctl net is literally just an alias for lctl network, they're the same thing, twins fr fr 💕

BUT (and this is the plot twist) — netctl lnet is the preferred command for configuring and unconfiguring network interfaces. so like, lctl network still works, but the cool kids are using netctl lnet. iykyk 😌

here's the vibe: the Lustre software automatically starts and stops LNet all on its own, zero effort required. but you can also manually stop or start it in a standalone manner, and that's lowkey iconic for two reasons:

• it's super useful for verifying that your networking setup actually works before you try to start the Lustre file system 👑 (vibe check your network first, always)
• it's necessary for Lustre routers, because routers only need the LND and LNet modules. that's it. that's the whole personality 🦋

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✨ OPTIONS ✨

• up — starts LNet 💅 the LNet modules must be loaded first though!! don't skip that step bestie, it will not go well 😭
• down — stops LNet 🌈
• configure — loads the LNet configuration 📥
• unconfigure — clears the LNet configuration 🧹 this step is necessary for standalone routers so they can remove LNet references before the LNet modules can be removed. no unconfigure = no module removal, periodt.

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🔥 NOTES 🔥

okay important stuff, listen up 📢

since Lustre 2.15.0, the lustre_rmmod script calls lnetctl lnet unconfigure or the lctl network down command internally to stop the LNet network interfaces. why does that matter?? because otherwise the lustre_rmmod utility does not work if you have manually run the lctl network up command. like. it just doesn't. 🙈

⚠️ BIG WARNING, FOR REAL ⚠️ attempting to remove lustre(7) modules before stopping the network may result in a crash or an LNet hang 💀 if that happens, the node must be rebooted (in most cases). so please, make sure that the Lustre network and the file system are stopped prior to unloading the modules. that's not a suggestion, that's the rule 💜

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🌟 EXAMPLES 🌟

to load the module and start LNet:

# modprobe lnet
# lctl network up
LNet configured

to stop LNet and remove the module:

# lctl network down
LNet ready to unload
# rmmod lnet

to load LNet configuration in standalone mode:

# lctl network configure
LNet configured

to clear the LNet configuration:

# lctl network unconfigure
LNet ready to unload

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🦋 AVAILABILITY 🦋

lctl network is a subcommand of lctl(8) and is distributed as part of the lustre(7) filesystem package since release 0.6.0 🎀 she's been around a while, an absolute veteran, we stan.

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👑 SEE ALSO 👑

lctl(8), lnetctl(8)

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okay that's the whole page bestie, you ate that 💅✨ this was Lustre, dated 2024-08-14, and you just finished reading LCTL-NETWORK(8) — go configure something iconic 🫶💖