Logread, sbin/fan_ctrl.sh, wrt1900ac v1

Installing and Using OpenWrt
1

I'm getting cron errors in logread from /sbin/fan_ctrl.sh on a WRT1900AC v1 (mamba).

    Sun Nov 28 11:00:00 2021 cron.err crond[1961]: USER root pid 3217 cmd /sbin/fan_ctrl.sh
    Sun Nov 28 11:05:00 2021 cron.err crond[1961]: USER root pid 4032 cmd /sbin/fan_ctrl.sh
    Sun Nov 28 11:10:00 2021 cron.err crond[1961]: USER root pid 5327 cmd /sbin/fan_ctrl.sh
    Sun Nov 28 11:15:00 2021 cron.err crond[1961]: USER root pid 5867 cmd /sbin/fan_ctrl.sh
    Sun Nov 28 11:20:00 2021 cron.err crond[1961]: USER root pid 6695 cmd /sbin/fan_ctrl.sh
    Sun Nov 28 11:25:00 2021 cron.err crond[1961]: USER root pid 7272 cmd /sbin/fan_ctrl.sh
    Sun Nov 28 11:30:00 2021 cron.err crond[1961]: USER root pid 8586 cmd /sbin/fan_ctrl.sh

There are no errors when running the script at the command line, so there's nothing to troubleshoot with the script, other than, perhaps the context cron provides.

The hardware has a fan for sure. And it works.

OpenWrt 21.02.1 output from `uname -a`:
`Linux OpenWrt 5.4.154 #0 SMP Sun Oct 24 09:01:35 2021 armv7l GNU/Linux`

Resulting output from when running /sbin/fan_ctrl.sh, after adding the -x switchon line 1:

+ cut -c1-2 /sys/class/hwmon/hwmon2/temp1_input
+ CPU_TEMP=71
+ cut -c1-2 /sys/class/hwmon/hwmon1/temp1_input
+ DDR_TEMP=55
+ cut -c1-2 /sys/class/hwmon/hwmon1/temp2_input
+ WIFI_TEMP=56
+ CPU_LOW=85
+ CPU_HIGH=95
+ DDR_LOW=65
+ DDR_HIGH=75
+ WIFI_LOW=100
+ WIFI_HIGH=115
+ '[' -d /sys/devices/pwm_fan ]
+ '[' -d /sys/devices/platform/pwm_fan ]
+ FAN_CTRL=/sys/devices/platform/pwm_fan/hwmon/hwmon0/pwm1
+ '[' 71 -ge 95 -o 55 -ge 75 -o 56 -ge 115 ]
+ '[' 71 -ge 85 -o 55 -ge 65 -o 56 -ge 100 ]
+ echo 0

it all looks fine. I've read this post but I don't need a procd fan replacement. The error is in cron.

the cron job seems to be the problem but the crontab looks just fine.

    # mamba fan script runs every 5 minutes
    */5 * * * * /sbin/fan_ctrl.sh

what's going on?

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3

Ok, that's an easy quick answer.

I'm not sure it's entirely logical or effective.

To save memory, we're gonna make logfiles larger than necessary? :joy: :joy: :joy:

Ok, so it's a benign crontab output.

Thanks.

1 Like
4

might be of interest

5

"logfile" is a static sized circular buffer in RAM...

1 Like
6

Indeed, @anomeome , I've seen some other posts about this from you.

I don't think I need those init scripts but the link you pointed out seems to be a good solution. It's buried in a post more than 700 replies long. :joy:

What's more interesting in is how you make the collapsible posts with code clips that can be expanded. It helps readability in forums.

7

@hnyman, this is a good feature and a good point. I didn't know but it sure makes sense. :+1: