Start/notes.ini Parameters/Console_Log_Max_Kbytes

Console_Log_Max_Kbytes

Parameter: Console_Log_Max_Kbytes
Short description: Sets the maximum size of the Domino console log file (console.log) and its mirror files in kilobytes. When the maximum size is reached, the file is overwritten in a circular fashion.

Profile

Parameter
Console_Log_Max_Kbytes
Component
Server (also workstation/Notes Client)
Category
Logging / Debug
Available since
Domino 6.x; currently documented in HCL Domino 10.0.1–14.5.1
Value format
Integer in kilobytes
Default without mirroring
not set = unlimited
Default with mirroring
100,000 KB (100 MB), maximum 1,000,000 KB (1 GB)

Description

Domino optionally writes its console output to the file IBM_TECHNICAL_SUPPORT/console.log. As long as Console_Log_Max_Kbytes is not set or is set to 0, this file grows unbounded — which is problematic on production servers (disk space, read performance during diagnostics).
With Console_Log_Max_Kbytes=<KB> you set an upper limit. Once it is reached, Domino starts overwriting new entries at the beginning of the file (circular logging). There is no automatic roll-over to a second file — that is what Console_Log_Mirror=1 is for.

Behavior in combination with mirroring

According to HCL Domino 10.0.1 Documentation ("Using console log mirroring"):
  • If Console_Log_Mirror=1 is active, the default for Console_Log_Max_Kbytes is 100,000 KB (100 MB).
  • The maximum is 1,000,000 KB (1 GB).
  • If Console_Log_Max_Kbytes is not specified, Domino behaves as if Console_Log_Max_Kbytes=100000 were set; the value is, however, not written back to notes.ini.
  • When the main file wraps, a new mirror file console1.log, console2.log, ... is created (see Console_Log_Mirror).

HCL recommendation for diagnostics

HCL Customer Support recommends in KB0086631 "Debug settings for SAML authentication with Domino web server" raising the limit for longer-running reproductions:
CONSOLE_LOG_MAX_KBYTES=50000
This raises console.log from the default 10 MB to 50 MB, which is typically sufficient for verbose debug output (DEBUG_SAML=31, WEBAUTH_VERBOSE_TRACE=1, etc.).

Examples

50 MB limit for auth/SAML diagnostics:
Console_Log_Enabled=1
Console_Log_Max_Kbytes=50000
100 MB limit together with mirroring:
Console_Log_Enabled=1
Console_Log_Mirror=1
Console_Log_Max_Kbytes=100000

Notes

  • Value is in KB, not MB — 100000 means 100,000 KB ≈ 100 MB; an accidental Console_Log_Max_Kbytes=100 would yield only 100 KB.
  • Takes effect only after server restart — changes are picked up at the next start.
  • No real rotation — without Console_Log_Mirror=1, the file is overwritten circularly, not rotated. If you need historical logs, you must enable mirroring.
  • Path — with debug_outfile you can move console.log to a different location.
  • Field experience — in some cases it has been reported that logging stops entirely once the maximum size is reached; in that case, additionally use mirroring to avoid this effect.
  • Companion parameters — Console_Log_Enabled, Console_Log_Mirror, Retain_Mirror_Logs, debug_outfile.

Sources (HCL Product Documentation)