FMS.LOG(5)

💾 fms.log(5) — like, the diary of the fms command 💖

Hey bestie, welcome to the manual page for fms.log from the AFS File Reference set (yep, that's the manual name, we're being fancy today ✨). This file is genuinely iconic — it's the receipts for everything fms does, and no cap, you're gonna want to read the whole thing. 🎀

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🌸 NAME 🌸

fms.log — it literally just records the output from the fms command. That's the whole vibe. 🫶

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✨ DESCRIPTION ✨

The fms.log file records the output generated by the fms command. And this output is not just random chatter — it includes two numbers that can appear in a tape device's entry in the /var/openafs/backup/tapeconfig file, on the Tape Coordinator machine that the tape device is attached to. Lowkey important. 👑

Those two numbers are:

• The capacity in bytes of the tape in the device. 💾
• The size in bytes of the end-of-file (EOF) marks — which people often just call filemarks — that the tape device writes. 🏷️

So when you're transferring the numbers recorded in this file over to the tapeconfig file, adjust them as specified in tapeconfig(5) — that's how you improve Tape Coordinator performance during dump operations. Do it, bestie. It's giving optimisation. 🔥

Now, about the file existing or not existing (the lore 😭):

• If fms.log does not already exist in the current working directory, the fms command interpreter creates it. In that case, the directory's mode bits must grant the "rwx" (read, write, and execute) permissions to the issuer of the command.
• If there's an existing file, the command interpreter overwrites it — so the file's mode bits only need to grant the w permission to the issuer of the fms command.

The fms command interpreter also writes similar information to the standard output stream as it runs, so you get the tea in real time. ☕

The file is in ASCII format. To display its contents, log onto the client machine and use a text editor or a file display command such as the UNIX cat command. 🐈

By default, the mode bits on the fms.log file grant the required "r" permission only to the owner — which is the local superuser "root" by default. So yeah, it's private. Respect the privacy. 🙈

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📝 OUTPUT 📝

The first few lines of the file provide a simple trace of the fms command interpreter's actions, specifying (for example) how many blocks it wrote on the tape. Cute little progress diary. 🦋

The final two lines in the file specify tape capacity and filemark size in bytes, using exactly this format:

Tape capacity is <tape_size> bytes
File marks are <filemark_size> bytes

Keep those *_size placeholders in mind — they're variables, not literal text, iykyk. 💅

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🌈 EXAMPLES 🌈

Here's an example of the fms.log file that specifies the tape used during the execution of the fms command had a capacity of 2,136,604,672 bytes, and that the tape device writes filemarks of size 1,910,220 bytes. Look at her go:

fms test started
wrote 130408 blocks
Tape capacity is 2136604672 bytes
File marks are 1910220 bytes

Ate. No crumbs. ⭐

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👀 SEE ALSO 👀

• tapeconfig(5)
• fms(8)

Go read those too, bestie — they're the supporting cast. 🧚

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©️ COPYRIGHT ©️

IBM Corporation 2000. <http://www.ibm.com/> All Rights Reserved.

This documentation is covered by the IBM Public License Version 1.0. It was converted from HTML to POD by software written by Chas Williams and Russ Allbery, based on work by Alf Wachsmann and Elizabeth Cassell. Giving credit where it's due, periodt. 💜

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And that's the whole page, bestie! 💖 This was OpenAFS, dated 2026-06-25, manual page FMS.LOG(5) — go forth and configure those tapes like the main character you are. 🎀✨👑