SGE_ALIASES(5)

💖 SGE_ALIASES(5) 💖

okay so bestie, gather round — this is the manual page for sge_aliases, aka the Grid Engine path aliasing file format, living its best life in the Grid Engine File Formats section of the manual. it's a file format page, not a command page, so we're reading vibes and rules here, not flags. let's go 🦋

✨ NAME ✨

sge_aliases — the Grid Engine path aliases file format. that's the whole name, short and slay 💅

🌸 DESCRIPTION 🌸

so the Grid Engine path aliasing facility is basically a glow-up for your file paths. it gives administrators and users the means to reflect complicated and inhomogeneous file system structures in distributed environments — think user home directories mounted under different paths on different hosts, the classic chaos 😭 — and it makes sure Grid Engine is able to locate the appropriate working directories for executing batch jobs. no cap, it's the fixer.

here's the tea: there is a system global path aliasing file and a user-local file. sge_aliases defines the format of both. yes, both. equal treatment, iconic.

• Blank lines, and lines with a '#' sign in the first column, are skipped. like, ignored entirely, we move on 💅
• Each line other than a blank line or a line with a leading '#' has to contain four strings separated by any number of blanks or tabs. four. not three, not five. four 🎀
• The first string specifies a source path, the second a submit host, the third an execution host, and the fourth the source path replacement.
• Both the submit and the execution host entries may consist of only a '*' sign, which matches any host. wildcard queen 👑

now, the way this actually kicks in: if the qsub(1) -cwd flag is specified (and only if — otherwise the user's home directory on the execution host is selected to execute the job), the path aliasing mechanism is activated, and the files are processed as follows:

• After qsub(1) has retrieved the physical current working directory path, the cluster global path aliasing file is read, if present. The user path aliases file is read afterwards, as if it were appended to the global file. stacking them like a little playlist 🎧
• Lines not to be skipped are read from the top of the file one by one, while the translations specified by those lines are stored if necessary.
• A translation is stored only if the submit host entry matches the host qsub(1) is executed on and if the source path forms the initial part of either the current working directory or of the source path replacements already stored. two conditions, both required, no skipping homework 📝
• As soon as both files are read, the stored path aliasing information is passed along with the submitted job. it travels with the job, like a lil carry-on 🧳
• On the execution host, the aliasing information will be evaluated. The leading part of the current working directory will be replaced by the source-path replacement if the execution-host entry of the path alias matches the executing host.

⚠️ note, and this one matters: the current working directory string will be changed in this case, and subsequent path aliases must match the replaced working directory path to be applied. so order lowkey matters here — once a path gets rewritten, later aliases are looking at the new version, not the original. iykyk 🙈

🌈 EXAMPLES 🌈

here's a simple little example of a path aliasing file resolving problems with inhomogeneous paths if automount(8) is used. chef's kiss, honestly 🍓

=====================================================
# Path Aliasing File
# src-path   sub-host   exec-host   replacement
/tmp_mnt/    *          *           /
# replaces any occurrence of /tmp_mnt/ by /
# if submitting or executing on any host.
# Thus paths on nfs server and clients are the same
=====================================================

see how the * * is doing the absolute most? any submit host, any exec host, and /tmp_mnt/ becomes /. paths on the nfs server and the clients end up the same, and everything is at peace ✨

🎀 FILES 🎀

• <sge_root>/<cell>/common/sge_aliases — global aliases file. the big one, the system-wide one 👑
• $HOME/.sge_aliases — user local aliases file. yours, personal, cute 🫶

🦋 SEE ALSO 🦋

• sge_intro(1)
• qsub(1)

go read those if you want the full lore, bestie.

💜 COPYRIGHT 💜

See sge_intro(1) for a full statement of rights and permissions. (yes, it's really that short. go check sge_intro(1) for the legal essay.)

and that's the whole page, periodt 💅 this was SGE 8.1.3pre, dated 2004-04-19 — vintage but still serving, fr fr. mwah, go alias something 🌸💖