Hi everyone,

Last night, around midnight, my Synchronet setup (running under Ubuntu) became unresponsive.

Typical log fragment:

Feb 20 07:22:42 synchronet synchronet: term Node 1 !Error 24 (Too many open files) opening: /sbbs/text/answer.msg
Feb 20 07:22:42 synchronet synchronet: term Node 1 !JavaScript : can't open /sbbs/exec/loginDD.js: No such file or directory
Feb 20 07:22:42 synchronet synchronet: term Node 1 !ERROR 24 (Too many open files) in exec.cpp line 662 (js_execfile) compiling "/sbbs/exec/loginDD.js" access=0

It wasn't just linked to loginDD.js - anything involving files would throw this error (including sbbsecho).

A stop / start has resolved the issue.... for now....

What's the best approach to hardening my installation against this?

Mewcenary.

---
þ Synchronet þ Extricate BBS - bbs.extricate.org
* Origin: Vertrauen - [vert/cvs/bbs].synchro.net (1:103/705)

Re: "Too many open files" under Linux
By: Mewcenary to All on Sun Feb 20 2022 07:45 am

Hi everyone,

Last night, around midnight, my Synchronet setup (running under Ubuntu) became unresponsive.

Typical log fragment:

Feb 20 07:22:42 synchronet synchronet: term Node 1 !Error 24 (Too many open files) opening: /sbbs/text/answer.msg
Feb 20 07:22:42 synchronet synchronet: term Node 1 !JavaScript : can't open /sbbs/exec/loginDD.js: No such file or directory
Feb 20 07:22:42 synchronet synchronet: term Node 1 !ERROR 24 (Too many open files) in exec.cpp line 662 (js_execfile) compiling "/sbbs/exec/loginDD.js" access=0

It wasn't just linked to loginDD.js - anything involving files would throw this error (including sbbsecho).

A stop / start has resolved the issue.... for now....

What's the best approach to hardening my installation against this?

Sounds like a bug (a file descriptor leak, usually open files, but could be open socket descriptors or other types of file descriptors that were not closed) somewhere. Using a tool such as 'lsof' if/when it happens again should help to identify the culprit.
--
digital man (rob)

Rush quote #55:
He'd like a lover's wings to fly on, to a tropic isle of Avalon .. Digital Man Norco, CA WX: 64.1øF, 48.0% humidity, 4 mph ESE wind, 0.00 inches rain/24hrs --- SBBSecho 3.14-Linux
* Origin: Vertrauen - [vert/cvs/bbs].synchro.net (1:103/705)

Re: "Too many open files" under Linux
By: Digital Man to Mewcenary on Sun Feb 20 2022 11:49 am

Sounds like a bug (a file descriptor leak, usually open files, but could be open socket descriptors or other types of file descriptors that were not closed) somewhere. Using a tool such as 'lsof' if/when it happens again should help to identify the culprit.

A preventative measure would be add to your /etc/security/limits.conf file:
* soft nofile 999999

There are other ways to modify a user's open file limit too: https://bobcares.com/blog/too-many-open-files/
--
digital man (rob)

Synchronet/BBS Terminology Definition #82:
Telix = Commercial MS-DOS and Windows communications/terminal program
Norco, CA WX: 64.7øF, 48.0% humidity, 4 mph SSE wind, 0.00 inches rain/24hrs --- SBBSecho 3.14-Linux
* Origin: Vertrauen - [vert/cvs/bbs].synchro.net (1:103/705)