• "Too many open files" under Linux

    From Mewcenary@VERT/EXTRICAT to All on Sunday, February 20, 2022 07:45:09
    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
  • From Digital Man@VERT to Mewcenary on Sunday, February 20, 2022 11:49:47
    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 ---
    þ Synchronet þ Vertrauen þ Home of Synchronet þ [vert/cvs/bbs].synchro.net
  • From Digital Man@VERT to Mewcenary on Sunday, February 20, 2022 11:59:58
    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 ---
    þ Synchronet þ Vertrauen þ Home of Synchronet þ [vert/cvs/bbs].synchro.net