RARP(8)

📦
version 981107 · 4 versions
, in epel 10, epel 9, fedora 43, fedora 44

💖 RARP(8) 💖

okay bestie, sit down, hydrate, and let me tell you about rarpd — the Reverse Address Resolution Protocol (RARP) daemon. yes it's a mouthful. yes it's iconic. let's go 🫶

✨ NAME ✨

rarpd — the Reverse Address Resolution Protocol (RARP) daemon. she serves. she responds. she's the reason your little boot-time babies get their IPs 💅

🌸 SYNOPSIS 🌸

rarpd [-aAvde] [-b bootdir ] [ interface ]

🦋 DESCRIPTION 🦋

so Rarpd is a daemon and her whole job is responding to RARP requests. some machines, when they boot up, literally do not know their own IP address (embarrassing, but valid) so they use RARP to find out. the way it works: the machine shows up with its Ethernet address, and rarpd looks that up and hands back the matching IP address. no cap 🔥

where does she find the IP? she checks the ethers database — that's either the /etc/ethers file or a NIS+ lookup — and if the ethers database gives her a hostname instead of an IP address, she does a DNS lookup to turn it into one. multi-step queen 👑

and here's the extra layer, bestie: by default rarpd ALSO checks whether a bootable image exists in the TFTP boot directory (usually /tftpboot) before she'll respond to the RARP request. the image name has to start with the IP address written in hexadecimal uppercase letters. she's not just handing out IPs to anybody — she's doing a whole vibe check first ✨

💅 OPTIONS 💅

  • -a — do not bind to the interface. just… don't. she's free 🦋
  • -A — respond to ARP requests as well as RARP requests. she does both, she contains multitudes 💖
  • -v — verbose mode. tell the user what is going on, because the user deserves to know 👑
  • -d — debugging mode. do not detach from the tty. she stays right there with you, watching, unbothered 😭
  • -e — skip the check for a bootable image in the TFTP boot directory. heads up though: if this flag is NOT present, then even if the Ethernet address IS in the ethers database, but the bootable image for the resolved IP does not exist, rarpd will not respond to the request. no image, no answer, periodt 💀
  • -b bootdir — use bootdir instead of the default /tftpboot as the TFTP boot directory for those bootable image checks. your directory, your rules 🌈

👑 OBSOLETES 👑

this rarpd obsoletes the kernel rarp daemon that lived inside Linux kernels up to 2.2, which was controlled by the rarp(8) command. rip to her, but she's different 💀🕊️

🎀 FILES 🎀

  • /etc/ethers,
  • /etc/nsswitch.conf,
  • /tftpboot

🌟 SEE ALSO 🌟

ethers(5)

💜 AUTHORS 💜

  • Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
  • Jakub Jelinek, <jakub@redhat.com>

and that's the whole page, bestie!! this gorgeous thing is rarpd, from the Linux Programmer's Manual, dated 7 April 2000, and it's still serving looks in RARP(8). mwah, stan forever 🫶✨🎀

📦 where this page comes from