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.

asked Feb 11 '16 at 12:17

Hemant

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bumped to the homepage by Community♦ 7 mins ago

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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.

asked Feb 11 '16 at 12:17

Hemant

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 |

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.

asked Feb 11 '16 at 12:17

Hemant

3318

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

Hemant

3318

asked Feb 11 '16 at 12:17

Hemant

3318

asked Feb 11 '16 at 12:17

Hemant

3318

asked Feb 11 '16 at 12:17

Hemant

3318

asked Feb 11 '16 at 12:17

Hemant

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 |

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'

edited Feb 11 '16 at 15:48

answered Feb 11 '16 at 15:39

marcarand

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
1

active

oldest

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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'

edited Feb 11 '16 at 15:48

answered Feb 11 '16 at 15:39

marcarand

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'

edited Feb 11 '16 at 15:48

answered Feb 11 '16 at 15:39

marcarand

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'

edited Feb 11 '16 at 15:48

answered Feb 11 '16 at 15:39

marcarand

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'

edited Feb 11 '16 at 15:48

answered Feb 11 '16 at 15:39

marcarand

edited Feb 11 '16 at 15:48

answered Feb 11 '16 at 15:39

marcarand

answered Feb 11 '16 at 15:39

marcarand

answered Feb 11 '16 at 15:39

marcarand

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

add a comment |

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