How to dump the dmesg AKA Kernel logs to a single .txt file from the kernel boot?
I am trying to understand the SATA Host-Device Communication and for that I have put a lot of debug messages in the kernel driver code.
Now messages are in such a huge amount that I am not able to see the initial messages of the device enumeration in the dmesg log. For the same I have modified CONFIG_LOG_BUF_SHIFT(=21) config variable to increase the ring buffer size from where dmesg takes the message but still I am facing the same issue.
So, Is there any method available by which I can log all the dmesg from the kernel boot in to a specific file?
Thanks for the Help in advance.
kernel linux-kernel drivers debugging
asked Feb 11 '16 at 12:17
HemantHemant
3318
bumped to the homepage by Community♦ 7 mins ago
This question has answers that may be good or bad; the system has marked it active so that they can be reviewed.
add a comment |
I am trying to understand the SATA Host-Device Communication and for that I have put a lot of debug messages in the kernel driver code.
Now messages are in such a huge amount that I am not able to see the initial messages of the device enumeration in the dmesg log. For the same I have modified CONFIG_LOG_BUF_SHIFT(=21) config variable to increase the ring buffer size from where dmesg takes the message but still I am facing the same issue.
So, Is there any method available by which I can log all the dmesg from the kernel boot in to a specific file?
Thanks for the Help in advance.
kernel linux-kernel drivers debugging
asked Feb 11 '16 at 12:17
HemantHemant
3318
bumped to the homepage by Community♦ 7 mins ago
This question has answers that may be good or bad; the system has marked it active so that they can be reviewed.
add a comment |
I am trying to understand the SATA Host-Device Communication and for that I have put a lot of debug messages in the kernel driver code.
Now messages are in such a huge amount that I am not able to see the initial messages of the device enumeration in the dmesg log. For the same I have modified CONFIG_LOG_BUF_SHIFT(=21) config variable to increase the ring buffer size from where dmesg takes the message but still I am facing the same issue.
So, Is there any method available by which I can log all the dmesg from the kernel boot in to a specific file?
Thanks for the Help in advance.
kernel linux-kernel drivers debugging
asked Feb 11 '16 at 12:17
HemantHemant
3318
I am trying to understand the SATA Host-Device Communication and for that I have put a lot of debug messages in the kernel driver code.
Now messages are in such a huge amount that I am not able to see the initial messages of the device enumeration in the dmesg log. For the same I have modified CONFIG_LOG_BUF_SHIFT(=21) config variable to increase the ring buffer size from where dmesg takes the message but still I am facing the same issue.
So, Is there any method available by which I can log all the dmesg from the kernel boot in to a specific file?
Thanks for the Help in advance.
kernel linux-kernel drivers debugging
kernel linux-kernel drivers debugging
asked Feb 11 '16 at 12:17
HemantHemant
3318
asked Feb 11 '16 at 12:17
HemantHemant
3318
asked Feb 11 '16 at 12:17
HemantHemant
3318
asked Feb 11 '16 at 12:17
HemantHemant
3318
asked Feb 11 '16 at 12:17
HemantHemant
3318
3318
bumped to the homepage by Community♦ 7 mins ago
This question has answers that may be good or bad; the system has marked it active so that they can be reviewed.
bumped to the homepage by Community♦ 7 mins ago
This question has answers that may be good or bad; the system has marked it active so that they can be reviewed.
add a comment |
add a comment |
1 Answer
1
active
oldest
votes
You can use:
cat /var/log/dmesg > file.txt
and use:
head /var/log/dmesg
if you want to see the first lines of dmesg.
See too 'man head' for more specifications.
The '>' symbol redirect the ouput of 'cat' to the 'file.txt'
answered Feb 11 '16 at 15:39
marcarandmarcarand
13
Thanks for the reply this method I know and tried but it didn't help I want all the messages from start of dmesg. e.g. from "[ 0.000000] Initializing cgroup subsys cpuset"
– Hemant
Feb 12 '16 at 4:36
add a comment |
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1 Answer
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1 Answer
1
active
oldest
votes
active
oldest
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active
oldest
votes
You can use:
cat /var/log/dmesg > file.txt
and use:
head /var/log/dmesg
if you want to see the first lines of dmesg.
See too 'man head' for more specifications.
The '>' symbol redirect the ouput of 'cat' to the 'file.txt'
answered Feb 11 '16 at 15:39
marcarandmarcarand
13
Thanks for the reply this method I know and tried but it didn't help I want all the messages from start of dmesg. e.g. from "[ 0.000000] Initializing cgroup subsys cpuset"
– Hemant
Feb 12 '16 at 4:36
add a comment |
You can use:
cat /var/log/dmesg > file.txt
and use:
head /var/log/dmesg
if you want to see the first lines of dmesg.
See too 'man head' for more specifications.
The '>' symbol redirect the ouput of 'cat' to the 'file.txt'
answered Feb 11 '16 at 15:39
marcarandmarcarand
13
Thanks for the reply this method I know and tried but it didn't help I want all the messages from start of dmesg. e.g. from "[ 0.000000] Initializing cgroup subsys cpuset"
– Hemant
Feb 12 '16 at 4:36
add a comment |
You can use:
cat /var/log/dmesg > file.txt
and use:
head /var/log/dmesg
if you want to see the first lines of dmesg.
See too 'man head' for more specifications.
The '>' symbol redirect the ouput of 'cat' to the 'file.txt'
answered Feb 11 '16 at 15:39
marcarandmarcarand
13
You can use:
cat /var/log/dmesg > file.txt
and use:
head /var/log/dmesg
if you want to see the first lines of dmesg.
See too 'man head' for more specifications.
The '>' symbol redirect the ouput of 'cat' to the 'file.txt'
answered Feb 11 '16 at 15:39
marcarandmarcarand
13
edited Feb 11 '16 at 15:48
answered Feb 11 '16 at 15:39
marcarandmarcarand
13
answered Feb 11 '16 at 15:39
marcarandmarcarand
13
answered Feb 11 '16 at 15:39
marcarandmarcarand
13
13
Thanks for the reply this method I know and tried but it didn't help I want all the messages from start of dmesg. e.g. from "[ 0.000000] Initializing cgroup subsys cpuset"
– Hemant
Feb 12 '16 at 4:36
add a comment |
Thanks for the reply this method I know and tried but it didn't help I want all the messages from start of dmesg. e.g. from "[ 0.000000] Initializing cgroup subsys cpuset"
– Hemant
Feb 12 '16 at 4:36
Thanks for the reply this method I know and tried but it didn't help I want all the messages from start of dmesg. e.g. from "[ 0.000000] Initializing cgroup subsys cpuset"
– Hemant
Feb 12 '16 at 4:36
Thanks for the reply this method I know and tried but it didn't help I want all the messages from start of dmesg. e.g. from "[ 0.000000] Initializing cgroup subsys cpuset"
– Hemant
Feb 12 '16 at 4:36
add a comment |
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