Last Reboot commands don't agree
Different commands about showing last reboot have different opinions. Who is right?
# uptime
10:05:31 up 90 days, 12:59, 2 users, load average: 0.04, 0.02, 0.00
# who -b
system boot 2018-11-22 21:05
# last reboot
wtmp begins Sat Feb 2 01:59:42 2019
reboot
asked Feb 21 at 9:35
DimiDakDimiDak
1213
add a comment |
Different commands about showing last reboot have different opinions. Who is right?
# uptime
10:05:31 up 90 days, 12:59, 2 users, load average: 0.04, 0.02, 0.00
# who -b
system boot 2018-11-22 21:05
# last reboot
wtmp begins Sat Feb 2 01:59:42 2019
reboot
asked Feb 21 at 9:35
DimiDakDimiDak
1213
add a comment |
Different commands about showing last reboot have different opinions. Who is right?
# uptime
10:05:31 up 90 days, 12:59, 2 users, load average: 0.04, 0.02, 0.00
# who -b
system boot 2018-11-22 21:05
# last reboot
wtmp begins Sat Feb 2 01:59:42 2019
reboot
asked Feb 21 at 9:35
DimiDakDimiDak
1213
Different commands about showing last reboot have different opinions. Who is right?
# uptime
10:05:31 up 90 days, 12:59, 2 users, load average: 0.04, 0.02, 0.00
# who -b
system boot 2018-11-22 21:05
# last reboot
wtmp begins Sat Feb 2 01:59:42 2019
reboot
reboot
asked Feb 21 at 9:35
DimiDakDimiDak
1213
asked Feb 21 at 9:35
DimiDakDimiDak
1213
asked Feb 21 at 9:35
DimiDakDimiDak
1213
asked Feb 21 at 9:35
DimiDakDimiDak
1213
asked Feb 21 at 9:35
DimiDakDimiDak
1213
1213
add a comment |
add a comment |
2 Answers
2
active
oldest
votes
They are all correct.
uptimeshows that the system has been up for 90 days and some
hours.
who -bsays the system was booted 2018-11-22 21:05 .. 90
days and some hours ago.
last rebootsays that the wtmp log file was rolled over or trunctaded at Sat Feb 2 01:59:42 2019, so it don't contain a reboot record.
answered Feb 21 at 9:44
Soren ASoren A
3,4781924
Thanx, I didn't get the last one though..
– DimiDak
Feb 21 at 11:44
1
It is explaining that wtmp does not reach all the way back to the last boot.
– Chris Stratton
Feb 21 at 21:43
add a comment |
The uptime command is telling you the current time, followed by the length of time the system has been running. In your example this shows the system has been up for 90 days, 12 hours and 59 minutes.
who -b is giving you a date and time that corresponds to the same boot time. There's only a difference of seconds there, which I presume is the time taken between commands.
The last reboot command uses the /var/log/wtmp file to determine the last boot. This log file has been rotated since the last boot took place, so does not contain information about the last boot. There is likely an old version of wtmp, such as /var/log/wtmp.1 that you can also query with:
last reboot -f /var/log/wtmp.1
Unfortunately it's unlikely that will contain details of your last reboot either due to the time frame.
answered Feb 21 at 9:45
ArronicalArronical
13.6k84892
Thanx, so what is "last reboot" good to use for?
– DimiDak
Feb 21 at 11:45
3
It can tell you what the last reboot was, but it has to be recent enough that it's still available in the recent versions of the wtmp file. There must be a way to reconfigure how many wtmp files are saved. If you reboot your server now, then issuelast reboot, it will show up in the output. The current output just means there are no recorded reboots in wtmp.
– Arronical
Feb 21 at 11:49
add a comment |
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2 Answers
2
active
oldest
votes
2 Answers
2
active
oldest
votes
active
oldest
votes
active
oldest
votes
They are all correct.
uptimeshows that the system has been up for 90 days and some
hours.
who -bsays the system was booted 2018-11-22 21:05 .. 90
days and some hours ago.
last rebootsays that the wtmp log file was rolled over or trunctaded at Sat Feb 2 01:59:42 2019, so it don't contain a reboot record.
answered Feb 21 at 9:44
Soren ASoren A
3,4781924
Thanx, I didn't get the last one though..
– DimiDak
Feb 21 at 11:44
1
It is explaining that wtmp does not reach all the way back to the last boot.
– Chris Stratton
Feb 21 at 21:43
add a comment |
They are all correct.
uptimeshows that the system has been up for 90 days and some
hours.
who -bsays the system was booted 2018-11-22 21:05 .. 90
days and some hours ago.
last rebootsays that the wtmp log file was rolled over or trunctaded at Sat Feb 2 01:59:42 2019, so it don't contain a reboot record.
answered Feb 21 at 9:44
Soren ASoren A
3,4781924
Thanx, I didn't get the last one though..
– DimiDak
Feb 21 at 11:44
1
It is explaining that wtmp does not reach all the way back to the last boot.
– Chris Stratton
Feb 21 at 21:43
add a comment |
They are all correct.
uptimeshows that the system has been up for 90 days and some
hours.
who -bsays the system was booted 2018-11-22 21:05 .. 90
days and some hours ago.
last rebootsays that the wtmp log file was rolled over or trunctaded at Sat Feb 2 01:59:42 2019, so it don't contain a reboot record.
answered Feb 21 at 9:44
Soren ASoren A
3,4781924
They are all correct.
uptimeshows that the system has been up for 90 days and some
hours.
who -bsays the system was booted 2018-11-22 21:05 .. 90
days and some hours ago.
last rebootsays that the wtmp log file was rolled over or trunctaded at Sat Feb 2 01:59:42 2019, so it don't contain a reboot record.
answered Feb 21 at 9:44
Soren ASoren A
3,4781924
answered Feb 21 at 9:44
Soren ASoren A
3,4781924
answered Feb 21 at 9:44
Soren ASoren A
3,4781924
answered Feb 21 at 9:44
Soren ASoren A
3,4781924
3,4781924
Thanx, I didn't get the last one though..
– DimiDak
Feb 21 at 11:44
1
It is explaining that wtmp does not reach all the way back to the last boot.
– Chris Stratton
Feb 21 at 21:43
add a comment |
Thanx, I didn't get the last one though..
– DimiDak
Feb 21 at 11:44
1
It is explaining that wtmp does not reach all the way back to the last boot.
– Chris Stratton
Feb 21 at 21:43
Thanx, I didn't get the last one though..
– DimiDak
Feb 21 at 11:44
Thanx, I didn't get the last one though..
– DimiDak
Feb 21 at 11:44
1
1
It is explaining that wtmp does not reach all the way back to the last boot.
– Chris Stratton
Feb 21 at 21:43
It is explaining that wtmp does not reach all the way back to the last boot.
– Chris Stratton
Feb 21 at 21:43
add a comment |
The uptime command is telling you the current time, followed by the length of time the system has been running. In your example this shows the system has been up for 90 days, 12 hours and 59 minutes.
who -b is giving you a date and time that corresponds to the same boot time. There's only a difference of seconds there, which I presume is the time taken between commands.
The last reboot command uses the /var/log/wtmp file to determine the last boot. This log file has been rotated since the last boot took place, so does not contain information about the last boot. There is likely an old version of wtmp, such as /var/log/wtmp.1 that you can also query with:
last reboot -f /var/log/wtmp.1
Unfortunately it's unlikely that will contain details of your last reboot either due to the time frame.
answered Feb 21 at 9:45
ArronicalArronical
13.6k84892
Thanx, so what is "last reboot" good to use for?
– DimiDak
Feb 21 at 11:45
3
It can tell you what the last reboot was, but it has to be recent enough that it's still available in the recent versions of the wtmp file. There must be a way to reconfigure how many wtmp files are saved. If you reboot your server now, then issuelast reboot, it will show up in the output. The current output just means there are no recorded reboots in wtmp.
– Arronical
Feb 21 at 11:49
add a comment |
The uptime command is telling you the current time, followed by the length of time the system has been running. In your example this shows the system has been up for 90 days, 12 hours and 59 minutes.
who -b is giving you a date and time that corresponds to the same boot time. There's only a difference of seconds there, which I presume is the time taken between commands.
The last reboot command uses the /var/log/wtmp file to determine the last boot. This log file has been rotated since the last boot took place, so does not contain information about the last boot. There is likely an old version of wtmp, such as /var/log/wtmp.1 that you can also query with:
last reboot -f /var/log/wtmp.1
Unfortunately it's unlikely that will contain details of your last reboot either due to the time frame.
answered Feb 21 at 9:45
ArronicalArronical
13.6k84892
Thanx, so what is "last reboot" good to use for?
– DimiDak
Feb 21 at 11:45
3
It can tell you what the last reboot was, but it has to be recent enough that it's still available in the recent versions of the wtmp file. There must be a way to reconfigure how many wtmp files are saved. If you reboot your server now, then issuelast reboot, it will show up in the output. The current output just means there are no recorded reboots in wtmp.
– Arronical
Feb 21 at 11:49
add a comment |
The uptime command is telling you the current time, followed by the length of time the system has been running. In your example this shows the system has been up for 90 days, 12 hours and 59 minutes.
who -b is giving you a date and time that corresponds to the same boot time. There's only a difference of seconds there, which I presume is the time taken between commands.
The last reboot command uses the /var/log/wtmp file to determine the last boot. This log file has been rotated since the last boot took place, so does not contain information about the last boot. There is likely an old version of wtmp, such as /var/log/wtmp.1 that you can also query with:
last reboot -f /var/log/wtmp.1
Unfortunately it's unlikely that will contain details of your last reboot either due to the time frame.
answered Feb 21 at 9:45
ArronicalArronical
13.6k84892
The uptime command is telling you the current time, followed by the length of time the system has been running. In your example this shows the system has been up for 90 days, 12 hours and 59 minutes.
who -b is giving you a date and time that corresponds to the same boot time. There's only a difference of seconds there, which I presume is the time taken between commands.
The last reboot command uses the /var/log/wtmp file to determine the last boot. This log file has been rotated since the last boot took place, so does not contain information about the last boot. There is likely an old version of wtmp, such as /var/log/wtmp.1 that you can also query with:
last reboot -f /var/log/wtmp.1
Unfortunately it's unlikely that will contain details of your last reboot either due to the time frame.
answered Feb 21 at 9:45
ArronicalArronical
13.6k84892
answered Feb 21 at 9:45
ArronicalArronical
13.6k84892
answered Feb 21 at 9:45
ArronicalArronical
13.6k84892
answered Feb 21 at 9:45
ArronicalArronical
13.6k84892
13.6k84892
Thanx, so what is "last reboot" good to use for?
– DimiDak
Feb 21 at 11:45
3
It can tell you what the last reboot was, but it has to be recent enough that it's still available in the recent versions of the wtmp file. There must be a way to reconfigure how many wtmp files are saved. If you reboot your server now, then issuelast reboot, it will show up in the output. The current output just means there are no recorded reboots in wtmp.
– Arronical
Feb 21 at 11:49
add a comment |
Thanx, so what is "last reboot" good to use for?
– DimiDak
Feb 21 at 11:45
3
It can tell you what the last reboot was, but it has to be recent enough that it's still available in the recent versions of the wtmp file. There must be a way to reconfigure how many wtmp files are saved. If you reboot your server now, then issuelast reboot, it will show up in the output. The current output just means there are no recorded reboots in wtmp.
– Arronical
Feb 21 at 11:49
Thanx, so what is "last reboot" good to use for?
– DimiDak
Feb 21 at 11:45
Thanx, so what is "last reboot" good to use for?
– DimiDak
Feb 21 at 11:45
3
3
It can tell you what the last reboot was, but it has to be recent enough that it's still available in the recent versions of the wtmp file. There must be a way to reconfigure how many wtmp files are saved. If you reboot your server now, then issue
last reboot, it will show up in the output. The current output just means there are no recorded reboots in wtmp.– Arronical
Feb 21 at 11:49
It can tell you what the last reboot was, but it has to be recent enough that it's still available in the recent versions of the wtmp file. There must be a way to reconfigure how many wtmp files are saved. If you reboot your server now, then issue
last reboot, it will show up in the output. The current output just means there are no recorded reboots in wtmp.– Arronical
Feb 21 at 11:49
add a comment |
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