It's a remote server so no GUI or fancy stuff installed, I connect to that host using SSH.
For security reasons I suppose, I cannot use the 'date -s' command to change the local server's current time.
$ cat /etc/issues ==> Ubuntu 10.04 LTS
$ uname -r ==> 2.6.32-042stab037.1
$ cat $SHELL ==> /bin/bash
'date' shows me time that is about 10 minutes early, I tried linking the right time from /usr/share/zoneinfo (New york in my case) to /etc/localtime, but nothing really changed, my clock is still 10 minutes unsynchronized.
Do I have to generate a new time zone binary using zic? Yes? how? no? What else could I try ?
Thanks a bunch in advance.
/s
Use adjtimex(8) to set the system clock of a running system. It will smoothly adjust the time and not leave any scary gaps as date would. The syntax for using it is quite beyond me, however, so I just use ntp and forget it.
If your clock issues persists accross reboots you will need to reset the hardware clock with hwclock as well.
Did you think about installing a ntp daemon to keep your time synchronized to avoid those time slicing ?
Ntpd is a good starting point (it is provided in debian packages ntp and openntpd)
You'll have to set a server reference (usually ntp.pool.org, but you can change it if you need) and then, launch it on machine startup.... and let him do the job (ie : keep the time synchronized)
Related
My MacBook spontaneously wakes up from sleep mode with high fan activity.
I want to do a investigate this in RTC or power settings? Or by strace-ing of processes, etc (using some process/kernel magic!).
Hint: It is probably managed by "rtcwake".
I am not even sure if this is a scheduled task, or from a WiFi wakeup, or something else.
I don't want guesses about what usually causes this in Mojave, etc. Instead:
I need to do a systematic investigation on this on my MacOS (Mojave). Linux-related answers are also appreciated.
This is about system standby, sleep-mode, suspended mode. (Note that this is not about standup and wakeup of individual processes. The whole laptop turns on spontaneously.)
Reading the log file is the best way to debug the problem.
So, try this command in your Terminal to fetch the system logs,
this will tell you "wake up" history.
log show --style syslog | fgrep "Wake reason: EC.LidOpen"
To see the wake reason:
For macOS Sierra, Mojave, Catalina, and newer
log show |grep -i "Wake reason"
Or for MacOS El Capitan, Yosemite, Mavericks, and older
syslog |grep -i "Wake reason"
This will look like:
MacBookPro kernel[0] : Wake reason = OHC1
MacBookPro kernel[0] : Wake reason = PWRB
MacBookPro kernel[0] : Wake reason = EHC2
MacBookPro kernel[0] : Wake reason = OHC1
So what do these wake reason codes mean?
OHC: stands for Open Host Controller, is usually USB or Firewire. If you see OHC1 or OHC2 it is almost certainly an external USB keyboard or mouse that has woken up the machine.
EHC: standing for Enhanced Host Controller, is another USB interface, but can also be wireless devices and bluetooth since they are also on the USB bus of a Mac.
USB: a USB device woke the machine up
LID0: this is literally the lid of your MacBook or MacBook Pro when you open the lid the machine wakes up from sleep.
PWRB: PWRB stands for Power Button, which is the physical power button on your Mac
RTC: Real Time Clock Alarm, is generally from wake-on-demand services like when you schedule sleep and wake on a Mac via the Energy Saver control panel. It can also be from launchd setting, user applications, backups, and other scheduled events.
There may be some other codes (like PCI, GEGE, etc) but the above are the ones that most people will encounter in the system logs. Once you find out these codes, you can really narrow down what is causing your Mac to wake up from sleep seemingly at random.
Hope this will help :)
This answer is based on Linux, so it might not apply strictly to Mac.
To determine whether rtcwake is responsible for your MacOS wakeups, you could replace the executable (in my Ubutnu it is /usr/sbin/rtcwake) with a wrapper script that leaves a sign of rtcwake having run, e.g.
$ cd /usr/sbin/rtcwake
$ sudo mv rtcwake rtcwake_orig
and then write script /usr/sbin/rtcwake containing
#!/bin/bash
touch $HOME/rtcwake_ran
/usr/sbin/rtcwake_orig
Variants of the script would depend on your shell.
In particular, in the last line you would possibly run rtcwake in some alternative way, so as to not own the process (nohup / disown).
See https://unix.stackexchange.com/questions/152310/how-to-correctly-start-an-application-from-a-shell
To inspect possible causes of wakeup, you can check various relevant logs, at /var/log.
E.g., syslog*, acpi*.
See also https://unix.stackexchange.com/questions/83036/where-is-the-log-for-acpi-events
Do you have wakeonlan?
Here I am documenting my systematic approach. It is loosely based on, and initiated by, the answer by #vijay-rajpurohit, which is in turn based on comment by #Robert #1431720 . Note that the final result is particular to my MacOS machine, based on the logs shown below. It will be different in your MacOS.
In first attempt, I first checked the logs using: log show --style syslog | grep ... but it is taking too long. I accidentally checked /var/log/wifi.log after exploring the /var/log/ (I am also curious about /var/log/powermanagement/*.asl).
This turned out to be most useful:
cat /var/log/wifi.log|grep -i "Wake reason"
Then found this line: (note the EC. bit)
Thu Apr 23 22:41:32.359 Info: <airportd[219]> _systemWokenByWiFi: System wake reason: <EC.ARPT>, was woken by WiFi
Then googled for EC.ARPT, I found the following commands:
pmset -g log Useful stats about "Total Sleep/Wakes since boot".
pmset -g assertions This turned out to show the full answer to this question:
2020-04-24 02:23:38 +0100
Assertion status system-wide:
BackgroundTask 1
ApplePushServiceTask 0
UserIsActive 1
PreventUserIdleDisplaySleep 0
PreventSystemSleep 0
ExternalMedia 0
PreventUserIdleSystemSleep 0
NetworkClientActive 0
Listed by owning process:
pid 111(hidd): [0x0000200a000986a9] 00:00:00 UserIsActive named: "com.apple.iohideventsystem.queue.tickle.4295010950.3"
pid 85(apsd): [0x0003b830000b90bd] 00:00:10 ApplePushServiceTask named: "com.apple.apsd-waitingformessages-push.apple.com"
Kernel Assertions: 0x100=MAGICWAKE
id=504 level=255 0x100=MAGICWAKE mod=24/04/2020, 01:57 description=en0 owner=en0
Idle sleep preventers: IODisplayWrangler
In short, in a systematic approach, I explored the following keywords based on the logs, and googled each :
EC.ARPT (example link)
iohideventsystem (example link)
MAGICWAKE (example link)
ApplePushServiceTask (see below)
Most informative item emerged from the output of pmset -g assertions. For example ApplePushServiceTask in the following line:
pid 85(apsd): [0x0003b830000b90bd] 00:00:10 ApplePushServiceTask named: "com.apple.apsd-waitingformessages-push.apple.com"
The solution that seems to work in my particular case (not a general solution) was to disable :
/System/Library/LaunchDaemons/com.apple.apsd.plist using launchctl. But this cannot be done until you do a csrutil disable in the safe mode. I don't write instructions here because it need caution and you need to enable it later.
(to be updated)
In a Linux CentOS 5 machine, I am running process.sh using a cronjob at #reboot, every day (the machine gets shut off every night and turned on every morning).
process.sh takes the 'date' of the computer, and writes it to a log file, then exits.
When I check the logfile, the timestamp in it says "Tue Jan 1 13:14:38 GMT 2008"
When I go to the console of the computer and give it the 'date' command, it prints the correct date.
My best guess is that my cronjob is running BEFORE the computer sets its correct time.
Is there a way to fix this?
The battery that powers the CMOS memory on your motherboard may have run out. Try replacing it by a fresh one. It should look something like this.
This advice is based on the fact that the date of your log entry is "Jan 1 2008" which looks conspicuously like an epoch your motherboard may use. However, the time-of-day 13:14:38 is a little off for this; while the 13 hour shift can be explained if you are in the correct time zone, the nearly 15 minute offset seems odd. Unless your computer takes that long to boot to the point where cron executes your job. And of course, the reason why you eventually see the correct time is probably that ntp fixed the system time, as others have noted.
i still want to check my Bootloader + Linux Startupcode for an embedded device. Therefore i want to catch the time for every command printed to the serial port.
I know there are programs like putty (which i can dearly recommend), getty, cutecom, picocom, screen etc. But none of these add timestamps to the incomming messages on the host screen (I'm not really talking about the date, more like how many ms have gone since the first output). It actually sounds not like a big deal.
I found out there is one script doing what i wanted to have, called grabserial but it's not working properly, since it's to slow to process the whole output. I discussed this problem in a different forum (if you want to know: grabserial problem but it's not part of the topic). So i can't use that script.
Now again: can you tell me a terminal for Linux which adds timestamps to every line, which was received from a Serial Port?
Thank you
[Edit:] I've found a pretty rough workaround with cereal, which wants to have some settings, since it locks the port everytime you use it. In the end, it adds the actual date and time, not the startup time and difftime between each step, so as you can see I'm still looking for an adequate solution.
This might come 3 years too late, but minicom (https://en.wikipedia.org/wiki/Minicom) supports timestamps for every line printed on the terminal. In Ubuntu it's directly available in the default repos.
You might want to look in to using strace to monitor the serial port. See How can I monitor data on a serial port in Linux?
If you are willing to build the binary by yourself, you can try a branched picocom (https://github.com/codepox/picocom). This is based on picocom 1.7 which is a little old.
I have forked and enhanced this picocom and made it be able to show either delta-time or wall-clock timestamp. You can find it here (https://github.com/tdwong/picocom-with-timestamp). You still have to build the binary by yourself.
Here is how I use it. Note, N is the command to enable/toggle timestamp.
$ picocom -b 115200 /dev/ttyUSB0
...
<ctrl-a> N # enable delta-time timestamp
<ctrl-a> N # toggle wall-clock timestamp
<ctrl-a> N # disable timestamp
tio found at https://tio.github.io provides various timestamp options:
-t, --timestamp
Enable line timestamp.
--timestamp-format <format>
Set timestamp format to any of the following timestamp formats:
24hour 24-hour format ("hh:mm:ss.sss")
24hour-start 24-hour format relative to start time
24hour-delta 24-hour format relative to previous timestamp
iso8601 ISO8601 format ("YYYY-MM-DDThh:mm:ss.sss")
Default format is 24hour
In your case, showing how much time has passed since start, that would be something like this:
tio -t --timestamp-format 24hour-start /dev/ttyUSB0
Settings can also be enabled in tio configuration file ~/.tioconfig
I believe that ExtraPuTTY is the solution you are looking for.
However, I wasn't clear if you wanted something to run ON Linux or just to be able to monitor it (SSH to Linux). If you didn't want a Windows solution, then I apologize.
Does anybody know how to see the processes for all users using top command in Cygwin (part of procps library under System).
I know this can be done in *nix but I am struggling in Cygwin. I have tried using pslist but it does not behave in a putty SSH console.
I need to have a solution where I can see a top like dialog using SSH. I do not have any NTLM SSO access to the Win2k3 guest at all so ssh is the only way in.
top only displays Cygwin processes. ps -W will list Windows processes as well.
Manytimes the command "tasklist" gets the job done more effectively. It built into windows, just make sure your System32 folder is part of your bash profile PATH. There is also procps itself. You should also try using mintty for your terminal. You could always try attaching any of these task apps to screen, and or using watch to poll the information.
It seems you can do something like:
wmic process get ProcessId,Name,UserModeTime,KernelModeTime /EVERY:1
The User and Kernel mode times there seem to be expressed in 1/10,000,000th of second.
You should be able to post-process that output to get the CPU-usage per second.
Here using cygwin's perl:
wmic process get ProcessId,Name,UserModeTime,KernelModeTime /EVERY:1 |
perl -lne '
if (/\S/) {
my ($k,$c,$p,$u) = split /\s{2,}/;
$n{"$p\t$c"}=$k+$u;
} else {
my %c;
for my $k (keys %n) {
$c{$k} = $n{$k} - $o{$k} if defined $o{$k}
}
print "$_\t" . $c{$_}/1e5 for (sort {$c{$b}<=>$c{$a}} keys %c)[0..20];
%o = %n; %n = undef; print ""
}'
Outputs something like:
0 System Idle Process 588.12377
2196 sh.exe 107.00075
248 svchost.exe 85.80055
7140 explorer.exe 26.52017
[...]
every second.
Note that if the System Idle Process shows just under 800% on an idle system, that's because your system has 8 CPU cores (well at least 8 threads) as that counts the CPU time of all CPUs.
Also note that the EVERY:1 above is a lie. wmic doesn't seem to give that output every second. More likely, it sleeps roughly 1 second between each report and doesn't compensate for the time it takes to compute the report. So in practice, it will run every 1 second and a bit which means those percentages are not very accurate and slightly overestimated.
How can I get a history of uptimes for my debian box? After a reboot, I dont see an option for the uptime command to print a history of uptimes. If it matters, I would like to use these uptimes for graphing a page in php to show my webservers uptime lengths between boots.
Update:
Not sure if it is based on a length of time or if last gets reset on reboot but I only get the most recent boot timestamp with the last command. last -x also does not return any further info. Sounds like a script is my best bet.
Update:
Uptimed is the information I am looking for, not sure how to grep that info in code. Managing my own script for a db sounds like the best fit for an application.
Install uptimed. It does exactly what you want.
Edit:
You can apparantly include it in a PHP page as easily as this:
<? system("/usr/local/bin/uprecords -a -B"); ?>
Examples
the last command will give you the reboot times of the system. You could take the difference between each successive reboot and that should give the uptime of the machine.
update
1800 INFORMATION answer is a better solution.
You could create a simple script which runs uptime and dumps it to a file.
uptime >> uptime.log
Then set up a cron job for it.
Try this out:
last | grep reboot
according to last manual page:
The pseudo user reboot logs in each time the system is rebooted.
Thus last reboot will show a log of all reboots since the log file
was created.
so last column of #last reboot command gives you uptime history:
#last reboot
reboot system boot **************** Sat Sep 21 03:31 - 08:27 (1+04:56)
reboot system boot **************** Wed Aug 7 07:08 - 08:27 (46+01:19)
This isn't stored between boots, but The Uptimes Project is a third-party option to track it, with software for a range of platforms.
Another tool available on Debian is uptimed which tracks uptimes between boots.
I would create a cron job to run at the required resolution (say 10 minutes) by entering the following [on one single line - I've just separated it for formatting purposes] in your crontab (cron -l to list, cron -e to edit).
0,10,20,30,40,50 * * * *
/bin/echo $(/bin/date +\%Y-\%m-\%d) $(/usr/bin/uptime)
>>/tmp/uptime.hist 2>&1
This appends the date, time and uptime to the uptime.hist file every ten minutes while the machine is running. You can then examine this file manually to figure out the information or write a script to process it as you see fit.
Whenever the uptime reduces, there's been a reboot since the previous record. When there are large gaps between lines (i.e., more than the expected ten minutes), the machine's been down during that time.
This information is not normally saved. However, you can sign up for an online service that will do this for you. You just install a client that will send your uptime to the server every 5 minutes and the site will present you with a graph of your uptimes:
http://uptimes-project.org/
i dont think this information is saved between reboots.
if shutting down properly you could run a command on shutdown that saves the uptime, that way you could read it back after booting back up.
Or you can use tuptime https://sourceforge.net/projects/tuptime/ for a total uptime time.
You can use tuptime, a simple command for report the total uptime in linux keeping it betwwen reboots.
http://sourceforge.net/projects/tuptime/
Since I haven't found an answer here that would help retroactively, maybe this will help someone.
kern.log (depending on your distribution) should log a timestamp.
It will be something like:
2019-01-28T06:25:25.459477+00:00 someserver kernel: [44114473.614361] somemessage
"44114473.614361" represents seconds since last boot, from that you can calculate the uptime without having to install anything.
Nagios can make even very beautiful diagrams about this.
Use Syslog
For anyone coming here searching for their past uptime.
The solution of #1800_Information is a good advise for the future, but I needed to find information for my past uptimes on a specific date.
Therefore I used syslog to determine when that day the system was started (first log entry of that day) and when the system was shutdown again.
Boot time
To get the system start time grep for the month and day and show only the first lines:
sudo grep "May 28" /var/log/syslog* | head
Shutdown time
To get the system shutdown time grep for the month and day and show only the last few lines:
sudo grep "May 28" /var/log/syslog* | tail