What is /etc/mtab in Linux?How to get the complete and exact list of mounted filesystems in Linux?What is the meaning of Scratchbox2?Why would someone choose FreeBSD over Linux?How are NTFS drives handled by Linux? Nothing is in fstab yet it's automounted. Nothing in mtab yet it's currently mountedWhat is the concept of Refresh in Linux, if there is soFinding correct information to update mtab and fstab?UUID in /etc/mtabHow to verify which line in /etc/mtab is not in use/etc/default/sw vs /etc/sw vs /etc/sw.d/Accidentally erased contents of /etc/fstab in Centos 7.2Why every device in Linux is a file or folder ? what are the advantages?
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What is /etc/mtab in Linux?
How to get the complete and exact list of mounted filesystems in Linux?What is the meaning of Scratchbox2?Why would someone choose FreeBSD over Linux?How are NTFS drives handled by Linux? Nothing is in fstab yet it's automounted. Nothing in mtab yet it's currently mountedWhat is the concept of Refresh in Linux, if there is soFinding correct information to update mtab and fstab?UUID in /etc/mtabHow to verify which line in /etc/mtab is not in use/etc/default/sw vs /etc/sw vs /etc/sw.d/Accidentally erased contents of /etc/fstab in Centos 7.2Why every device in Linux is a file or folder ? what are the advantages?
.everyoneloves__top-leaderboard:empty,.everyoneloves__mid-leaderboard:empty,.everyoneloves__bot-mid-leaderboard:empty margin-bottom:0;
What is /etc/mtab
in Linux?
Why is it needed and advantages of having it?
linux fstab
New contributor
add a comment |
What is /etc/mtab
in Linux?
Why is it needed and advantages of having it?
linux fstab
New contributor
Related: Is there a command to see where a disk is mounted?
– Kusalananda♦
Apr 23 at 17:35
I find it frustrating thatman 5 mtab
is missing.
– Weijun Zhou
Apr 23 at 17:48
2
Also: unix.stackexchange.com/q/24182/117549
– Jeff Schaller♦
Apr 23 at 18:08
add a comment |
What is /etc/mtab
in Linux?
Why is it needed and advantages of having it?
linux fstab
New contributor
What is /etc/mtab
in Linux?
Why is it needed and advantages of having it?
linux fstab
linux fstab
New contributor
New contributor
edited Apr 23 at 17:42
Kusalananda♦
144k18268449
144k18268449
New contributor
asked Apr 23 at 17:31
Sathish kumarSathish kumar
13723
13723
New contributor
New contributor
Related: Is there a command to see where a disk is mounted?
– Kusalananda♦
Apr 23 at 17:35
I find it frustrating thatman 5 mtab
is missing.
– Weijun Zhou
Apr 23 at 17:48
2
Also: unix.stackexchange.com/q/24182/117549
– Jeff Schaller♦
Apr 23 at 18:08
add a comment |
Related: Is there a command to see where a disk is mounted?
– Kusalananda♦
Apr 23 at 17:35
I find it frustrating thatman 5 mtab
is missing.
– Weijun Zhou
Apr 23 at 17:48
2
Also: unix.stackexchange.com/q/24182/117549
– Jeff Schaller♦
Apr 23 at 18:08
Related: Is there a command to see where a disk is mounted?
– Kusalananda♦
Apr 23 at 17:35
Related: Is there a command to see where a disk is mounted?
– Kusalananda♦
Apr 23 at 17:35
I find it frustrating that
man 5 mtab
is missing.– Weijun Zhou
Apr 23 at 17:48
I find it frustrating that
man 5 mtab
is missing.– Weijun Zhou
Apr 23 at 17:48
2
2
Also: unix.stackexchange.com/q/24182/117549
– Jeff Schaller♦
Apr 23 at 18:08
Also: unix.stackexchange.com/q/24182/117549
– Jeff Schaller♦
Apr 23 at 18:08
add a comment |
2 Answers
2
active
oldest
votes
% file /etc/mtab
/etc/mtab: symbolic link to ../proc/self/mounts
% file /proc/mounts
/proc/mounts: symbolic link to self/mounts
%
/etc/mtab
is a compatibility mechanism. Decades ago, Unix did not have a system call for reading the existing mount information. Instead, programs that mounted filesystems were expected to coöperatively and voluntarily maintain a table in /etc/mtab
of what was mounted where.
For obvious reasons, this was not an ideal mechanism.
Linux gained the notion of a "procfs", and one of the things that it gained was a kernel-maintained version of this table, in the form of a mounts
pseudo-regular file. The "system call" to read the mount information out of the kernel became an open-read-close sequence against that file, followed by parsing the result from human-readable to machine-readable form (something that has some subtle catches, as you can see from the bug reports from just over a fortnight ago).
/etc/mtab
thus has popularly become a symbolic link to /proc/mounts
, allowing programs that had hardwired that name to keep reading a mount table from that file, which the programs that mounted and unmounted filesystems no longer have to explicitly do anything themselves to keep up to date. (Some of them still will, though, if /etc/mtab
turns out to be a writable regular file. And there are a few corner cases where the normalized information in mounts
that lacks all non-kernel stuff is not quite what is needed; although they do not outweigh the general problems with /etc/mtab
.)
Each process can nowadays have its own individual view of what is mounted, and there are as a consequence now individual mounts
files for each process in the procfs, each process's own table being accessible to it via the self
symbolic link as self/mounts
, and /proc/mounts
is also now a compatibility mechanism. (Interestingly, neither per-process mounts
nor the format of mounts
are documented in the current Linux doco, although the similar mountinfo
pseudo-regular file is.)
SunOS/Solaris has a similar mechanism. The /etc/mnttab
file is actually a single-file filesystem, and in addition to reading the table, via an open file descriptor to that file, with the read()
system call, one can watch for mount point changes with poll()
and obtain various further pieces of information with ioctl()
.
In HP-UX, /etc/mnttab
is likewise the name of the file, but as of version 11 it was still a regular file whose contents were coöperatively maintained by the system utility programs.
AIX does not export a human-readable text table that programs have to parse, and there is no equivalent file. The BSDs, similarly, have fully-fledged system calls, getfsstat()
on FreeBSD and OpenBSD, for programs to obtain the mount table from the kernel in machine-readable form without marshalling it through a human-readable intermediate form.
Further reading
- Zygmunt Krynicki (2019-03-16). r in path confuses mount units. #12018. systemd issues.
- Zbigniew Jędrzejewski-Szmek (2019-04-04). [df] incorrect parsing of
/proc/self/mountinfo
with r in mount path. #35137. GNU coreutils bugs. /proc/mounts
. Documentation/filesystems/proc.txt. Linux 5.1.- Jonathan de Boyne Pollard (2019-02-28). Re: what is the purpose of
fstab-decode
. Bug #567071. Debian bugs. getfsstat()
. FreeBSD System Calls Manual. 2016-12-27.
In complement with my comment in the question here is themtab(5)
from the old days: man.cat-v.org/unix_8th/5/mtab.
– Weijun Zhou
Apr 23 at 19:20
2
not only/proc/mounts
, but/proc/self/mounts
is itself a compatibility mechanism now; it's only showing a subset of the info available in/proc/self/mountinfo
. The format of/proc/self/mounts
is documented inproc(5)
as identical tofstab(5)
– mosvy
Apr 24 at 2:35
though admittedly, fstab(5) only tells about spaces being replaced by octal escapes, while it's spaces, tabs, newlines and backslashes
– mosvy
Apr 24 at 3:08
I know pseudo files and regular files, but what is a pseudo regular file?
– gerrit
Apr 24 at 7:16
@gerrit it's a regular file which has size 0 but still contains data ;-)
– mosvy
Apr 24 at 8:37
|
show 1 more comment
According to man mount
:
The programs mount and umount traditionally maintained a list of currently mounted filesystems in the file /etc/mtab. This real mtab file is still supported, but on current Linux systems it is better to make it a symlink to /proc/mounts instead, because a regular mtab file maintained in userspace cannot reliably work with namespaces, containers and other advanced Linux features.
On mounting without recording in /etc/mtab
:
-n, --no-mtab
Mount without writing in /etc/mtab. This is necessary for example when /etc is on a read-only filesystem.
Many more nuances are given in the manual page.
add a comment |
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2 Answers
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% file /etc/mtab
/etc/mtab: symbolic link to ../proc/self/mounts
% file /proc/mounts
/proc/mounts: symbolic link to self/mounts
%
/etc/mtab
is a compatibility mechanism. Decades ago, Unix did not have a system call for reading the existing mount information. Instead, programs that mounted filesystems were expected to coöperatively and voluntarily maintain a table in /etc/mtab
of what was mounted where.
For obvious reasons, this was not an ideal mechanism.
Linux gained the notion of a "procfs", and one of the things that it gained was a kernel-maintained version of this table, in the form of a mounts
pseudo-regular file. The "system call" to read the mount information out of the kernel became an open-read-close sequence against that file, followed by parsing the result from human-readable to machine-readable form (something that has some subtle catches, as you can see from the bug reports from just over a fortnight ago).
/etc/mtab
thus has popularly become a symbolic link to /proc/mounts
, allowing programs that had hardwired that name to keep reading a mount table from that file, which the programs that mounted and unmounted filesystems no longer have to explicitly do anything themselves to keep up to date. (Some of them still will, though, if /etc/mtab
turns out to be a writable regular file. And there are a few corner cases where the normalized information in mounts
that lacks all non-kernel stuff is not quite what is needed; although they do not outweigh the general problems with /etc/mtab
.)
Each process can nowadays have its own individual view of what is mounted, and there are as a consequence now individual mounts
files for each process in the procfs, each process's own table being accessible to it via the self
symbolic link as self/mounts
, and /proc/mounts
is also now a compatibility mechanism. (Interestingly, neither per-process mounts
nor the format of mounts
are documented in the current Linux doco, although the similar mountinfo
pseudo-regular file is.)
SunOS/Solaris has a similar mechanism. The /etc/mnttab
file is actually a single-file filesystem, and in addition to reading the table, via an open file descriptor to that file, with the read()
system call, one can watch for mount point changes with poll()
and obtain various further pieces of information with ioctl()
.
In HP-UX, /etc/mnttab
is likewise the name of the file, but as of version 11 it was still a regular file whose contents were coöperatively maintained by the system utility programs.
AIX does not export a human-readable text table that programs have to parse, and there is no equivalent file. The BSDs, similarly, have fully-fledged system calls, getfsstat()
on FreeBSD and OpenBSD, for programs to obtain the mount table from the kernel in machine-readable form without marshalling it through a human-readable intermediate form.
Further reading
- Zygmunt Krynicki (2019-03-16). r in path confuses mount units. #12018. systemd issues.
- Zbigniew Jędrzejewski-Szmek (2019-04-04). [df] incorrect parsing of
/proc/self/mountinfo
with r in mount path. #35137. GNU coreutils bugs. /proc/mounts
. Documentation/filesystems/proc.txt. Linux 5.1.- Jonathan de Boyne Pollard (2019-02-28). Re: what is the purpose of
fstab-decode
. Bug #567071. Debian bugs. getfsstat()
. FreeBSD System Calls Manual. 2016-12-27.
In complement with my comment in the question here is themtab(5)
from the old days: man.cat-v.org/unix_8th/5/mtab.
– Weijun Zhou
Apr 23 at 19:20
2
not only/proc/mounts
, but/proc/self/mounts
is itself a compatibility mechanism now; it's only showing a subset of the info available in/proc/self/mountinfo
. The format of/proc/self/mounts
is documented inproc(5)
as identical tofstab(5)
– mosvy
Apr 24 at 2:35
though admittedly, fstab(5) only tells about spaces being replaced by octal escapes, while it's spaces, tabs, newlines and backslashes
– mosvy
Apr 24 at 3:08
I know pseudo files and regular files, but what is a pseudo regular file?
– gerrit
Apr 24 at 7:16
@gerrit it's a regular file which has size 0 but still contains data ;-)
– mosvy
Apr 24 at 8:37
|
show 1 more comment
% file /etc/mtab
/etc/mtab: symbolic link to ../proc/self/mounts
% file /proc/mounts
/proc/mounts: symbolic link to self/mounts
%
/etc/mtab
is a compatibility mechanism. Decades ago, Unix did not have a system call for reading the existing mount information. Instead, programs that mounted filesystems were expected to coöperatively and voluntarily maintain a table in /etc/mtab
of what was mounted where.
For obvious reasons, this was not an ideal mechanism.
Linux gained the notion of a "procfs", and one of the things that it gained was a kernel-maintained version of this table, in the form of a mounts
pseudo-regular file. The "system call" to read the mount information out of the kernel became an open-read-close sequence against that file, followed by parsing the result from human-readable to machine-readable form (something that has some subtle catches, as you can see from the bug reports from just over a fortnight ago).
/etc/mtab
thus has popularly become a symbolic link to /proc/mounts
, allowing programs that had hardwired that name to keep reading a mount table from that file, which the programs that mounted and unmounted filesystems no longer have to explicitly do anything themselves to keep up to date. (Some of them still will, though, if /etc/mtab
turns out to be a writable regular file. And there are a few corner cases where the normalized information in mounts
that lacks all non-kernel stuff is not quite what is needed; although they do not outweigh the general problems with /etc/mtab
.)
Each process can nowadays have its own individual view of what is mounted, and there are as a consequence now individual mounts
files for each process in the procfs, each process's own table being accessible to it via the self
symbolic link as self/mounts
, and /proc/mounts
is also now a compatibility mechanism. (Interestingly, neither per-process mounts
nor the format of mounts
are documented in the current Linux doco, although the similar mountinfo
pseudo-regular file is.)
SunOS/Solaris has a similar mechanism. The /etc/mnttab
file is actually a single-file filesystem, and in addition to reading the table, via an open file descriptor to that file, with the read()
system call, one can watch for mount point changes with poll()
and obtain various further pieces of information with ioctl()
.
In HP-UX, /etc/mnttab
is likewise the name of the file, but as of version 11 it was still a regular file whose contents were coöperatively maintained by the system utility programs.
AIX does not export a human-readable text table that programs have to parse, and there is no equivalent file. The BSDs, similarly, have fully-fledged system calls, getfsstat()
on FreeBSD and OpenBSD, for programs to obtain the mount table from the kernel in machine-readable form without marshalling it through a human-readable intermediate form.
Further reading
- Zygmunt Krynicki (2019-03-16). r in path confuses mount units. #12018. systemd issues.
- Zbigniew Jędrzejewski-Szmek (2019-04-04). [df] incorrect parsing of
/proc/self/mountinfo
with r in mount path. #35137. GNU coreutils bugs. /proc/mounts
. Documentation/filesystems/proc.txt. Linux 5.1.- Jonathan de Boyne Pollard (2019-02-28). Re: what is the purpose of
fstab-decode
. Bug #567071. Debian bugs. getfsstat()
. FreeBSD System Calls Manual. 2016-12-27.
In complement with my comment in the question here is themtab(5)
from the old days: man.cat-v.org/unix_8th/5/mtab.
– Weijun Zhou
Apr 23 at 19:20
2
not only/proc/mounts
, but/proc/self/mounts
is itself a compatibility mechanism now; it's only showing a subset of the info available in/proc/self/mountinfo
. The format of/proc/self/mounts
is documented inproc(5)
as identical tofstab(5)
– mosvy
Apr 24 at 2:35
though admittedly, fstab(5) only tells about spaces being replaced by octal escapes, while it's spaces, tabs, newlines and backslashes
– mosvy
Apr 24 at 3:08
I know pseudo files and regular files, but what is a pseudo regular file?
– gerrit
Apr 24 at 7:16
@gerrit it's a regular file which has size 0 but still contains data ;-)
– mosvy
Apr 24 at 8:37
|
show 1 more comment
% file /etc/mtab
/etc/mtab: symbolic link to ../proc/self/mounts
% file /proc/mounts
/proc/mounts: symbolic link to self/mounts
%
/etc/mtab
is a compatibility mechanism. Decades ago, Unix did not have a system call for reading the existing mount information. Instead, programs that mounted filesystems were expected to coöperatively and voluntarily maintain a table in /etc/mtab
of what was mounted where.
For obvious reasons, this was not an ideal mechanism.
Linux gained the notion of a "procfs", and one of the things that it gained was a kernel-maintained version of this table, in the form of a mounts
pseudo-regular file. The "system call" to read the mount information out of the kernel became an open-read-close sequence against that file, followed by parsing the result from human-readable to machine-readable form (something that has some subtle catches, as you can see from the bug reports from just over a fortnight ago).
/etc/mtab
thus has popularly become a symbolic link to /proc/mounts
, allowing programs that had hardwired that name to keep reading a mount table from that file, which the programs that mounted and unmounted filesystems no longer have to explicitly do anything themselves to keep up to date. (Some of them still will, though, if /etc/mtab
turns out to be a writable regular file. And there are a few corner cases where the normalized information in mounts
that lacks all non-kernel stuff is not quite what is needed; although they do not outweigh the general problems with /etc/mtab
.)
Each process can nowadays have its own individual view of what is mounted, and there are as a consequence now individual mounts
files for each process in the procfs, each process's own table being accessible to it via the self
symbolic link as self/mounts
, and /proc/mounts
is also now a compatibility mechanism. (Interestingly, neither per-process mounts
nor the format of mounts
are documented in the current Linux doco, although the similar mountinfo
pseudo-regular file is.)
SunOS/Solaris has a similar mechanism. The /etc/mnttab
file is actually a single-file filesystem, and in addition to reading the table, via an open file descriptor to that file, with the read()
system call, one can watch for mount point changes with poll()
and obtain various further pieces of information with ioctl()
.
In HP-UX, /etc/mnttab
is likewise the name of the file, but as of version 11 it was still a regular file whose contents were coöperatively maintained by the system utility programs.
AIX does not export a human-readable text table that programs have to parse, and there is no equivalent file. The BSDs, similarly, have fully-fledged system calls, getfsstat()
on FreeBSD and OpenBSD, for programs to obtain the mount table from the kernel in machine-readable form without marshalling it through a human-readable intermediate form.
Further reading
- Zygmunt Krynicki (2019-03-16). r in path confuses mount units. #12018. systemd issues.
- Zbigniew Jędrzejewski-Szmek (2019-04-04). [df] incorrect parsing of
/proc/self/mountinfo
with r in mount path. #35137. GNU coreutils bugs. /proc/mounts
. Documentation/filesystems/proc.txt. Linux 5.1.- Jonathan de Boyne Pollard (2019-02-28). Re: what is the purpose of
fstab-decode
. Bug #567071. Debian bugs. getfsstat()
. FreeBSD System Calls Manual. 2016-12-27.
% file /etc/mtab
/etc/mtab: symbolic link to ../proc/self/mounts
% file /proc/mounts
/proc/mounts: symbolic link to self/mounts
%
/etc/mtab
is a compatibility mechanism. Decades ago, Unix did not have a system call for reading the existing mount information. Instead, programs that mounted filesystems were expected to coöperatively and voluntarily maintain a table in /etc/mtab
of what was mounted where.
For obvious reasons, this was not an ideal mechanism.
Linux gained the notion of a "procfs", and one of the things that it gained was a kernel-maintained version of this table, in the form of a mounts
pseudo-regular file. The "system call" to read the mount information out of the kernel became an open-read-close sequence against that file, followed by parsing the result from human-readable to machine-readable form (something that has some subtle catches, as you can see from the bug reports from just over a fortnight ago).
/etc/mtab
thus has popularly become a symbolic link to /proc/mounts
, allowing programs that had hardwired that name to keep reading a mount table from that file, which the programs that mounted and unmounted filesystems no longer have to explicitly do anything themselves to keep up to date. (Some of them still will, though, if /etc/mtab
turns out to be a writable regular file. And there are a few corner cases where the normalized information in mounts
that lacks all non-kernel stuff is not quite what is needed; although they do not outweigh the general problems with /etc/mtab
.)
Each process can nowadays have its own individual view of what is mounted, and there are as a consequence now individual mounts
files for each process in the procfs, each process's own table being accessible to it via the self
symbolic link as self/mounts
, and /proc/mounts
is also now a compatibility mechanism. (Interestingly, neither per-process mounts
nor the format of mounts
are documented in the current Linux doco, although the similar mountinfo
pseudo-regular file is.)
SunOS/Solaris has a similar mechanism. The /etc/mnttab
file is actually a single-file filesystem, and in addition to reading the table, via an open file descriptor to that file, with the read()
system call, one can watch for mount point changes with poll()
and obtain various further pieces of information with ioctl()
.
In HP-UX, /etc/mnttab
is likewise the name of the file, but as of version 11 it was still a regular file whose contents were coöperatively maintained by the system utility programs.
AIX does not export a human-readable text table that programs have to parse, and there is no equivalent file. The BSDs, similarly, have fully-fledged system calls, getfsstat()
on FreeBSD and OpenBSD, for programs to obtain the mount table from the kernel in machine-readable form without marshalling it through a human-readable intermediate form.
Further reading
- Zygmunt Krynicki (2019-03-16). r in path confuses mount units. #12018. systemd issues.
- Zbigniew Jędrzejewski-Szmek (2019-04-04). [df] incorrect parsing of
/proc/self/mountinfo
with r in mount path. #35137. GNU coreutils bugs. /proc/mounts
. Documentation/filesystems/proc.txt. Linux 5.1.- Jonathan de Boyne Pollard (2019-02-28). Re: what is the purpose of
fstab-decode
. Bug #567071. Debian bugs. getfsstat()
. FreeBSD System Calls Manual. 2016-12-27.
edited Apr 24 at 7:48
answered Apr 23 at 19:16
JdeBPJdeBP
39k480187
39k480187
In complement with my comment in the question here is themtab(5)
from the old days: man.cat-v.org/unix_8th/5/mtab.
– Weijun Zhou
Apr 23 at 19:20
2
not only/proc/mounts
, but/proc/self/mounts
is itself a compatibility mechanism now; it's only showing a subset of the info available in/proc/self/mountinfo
. The format of/proc/self/mounts
is documented inproc(5)
as identical tofstab(5)
– mosvy
Apr 24 at 2:35
though admittedly, fstab(5) only tells about spaces being replaced by octal escapes, while it's spaces, tabs, newlines and backslashes
– mosvy
Apr 24 at 3:08
I know pseudo files and regular files, but what is a pseudo regular file?
– gerrit
Apr 24 at 7:16
@gerrit it's a regular file which has size 0 but still contains data ;-)
– mosvy
Apr 24 at 8:37
|
show 1 more comment
In complement with my comment in the question here is themtab(5)
from the old days: man.cat-v.org/unix_8th/5/mtab.
– Weijun Zhou
Apr 23 at 19:20
2
not only/proc/mounts
, but/proc/self/mounts
is itself a compatibility mechanism now; it's only showing a subset of the info available in/proc/self/mountinfo
. The format of/proc/self/mounts
is documented inproc(5)
as identical tofstab(5)
– mosvy
Apr 24 at 2:35
though admittedly, fstab(5) only tells about spaces being replaced by octal escapes, while it's spaces, tabs, newlines and backslashes
– mosvy
Apr 24 at 3:08
I know pseudo files and regular files, but what is a pseudo regular file?
– gerrit
Apr 24 at 7:16
@gerrit it's a regular file which has size 0 but still contains data ;-)
– mosvy
Apr 24 at 8:37
In complement with my comment in the question here is the
mtab(5)
from the old days: man.cat-v.org/unix_8th/5/mtab.– Weijun Zhou
Apr 23 at 19:20
In complement with my comment in the question here is the
mtab(5)
from the old days: man.cat-v.org/unix_8th/5/mtab.– Weijun Zhou
Apr 23 at 19:20
2
2
not only
/proc/mounts
, but /proc/self/mounts
is itself a compatibility mechanism now; it's only showing a subset of the info available in /proc/self/mountinfo
. The format of /proc/self/mounts
is documented in proc(5)
as identical to fstab(5)
– mosvy
Apr 24 at 2:35
not only
/proc/mounts
, but /proc/self/mounts
is itself a compatibility mechanism now; it's only showing a subset of the info available in /proc/self/mountinfo
. The format of /proc/self/mounts
is documented in proc(5)
as identical to fstab(5)
– mosvy
Apr 24 at 2:35
though admittedly, fstab(5) only tells about spaces being replaced by octal escapes, while it's spaces, tabs, newlines and backslashes
– mosvy
Apr 24 at 3:08
though admittedly, fstab(5) only tells about spaces being replaced by octal escapes, while it's spaces, tabs, newlines and backslashes
– mosvy
Apr 24 at 3:08
I know pseudo files and regular files, but what is a pseudo regular file?
– gerrit
Apr 24 at 7:16
I know pseudo files and regular files, but what is a pseudo regular file?
– gerrit
Apr 24 at 7:16
@gerrit it's a regular file which has size 0 but still contains data ;-)
– mosvy
Apr 24 at 8:37
@gerrit it's a regular file which has size 0 but still contains data ;-)
– mosvy
Apr 24 at 8:37
|
show 1 more comment
According to man mount
:
The programs mount and umount traditionally maintained a list of currently mounted filesystems in the file /etc/mtab. This real mtab file is still supported, but on current Linux systems it is better to make it a symlink to /proc/mounts instead, because a regular mtab file maintained in userspace cannot reliably work with namespaces, containers and other advanced Linux features.
On mounting without recording in /etc/mtab
:
-n, --no-mtab
Mount without writing in /etc/mtab. This is necessary for example when /etc is on a read-only filesystem.
Many more nuances are given in the manual page.
add a comment |
According to man mount
:
The programs mount and umount traditionally maintained a list of currently mounted filesystems in the file /etc/mtab. This real mtab file is still supported, but on current Linux systems it is better to make it a symlink to /proc/mounts instead, because a regular mtab file maintained in userspace cannot reliably work with namespaces, containers and other advanced Linux features.
On mounting without recording in /etc/mtab
:
-n, --no-mtab
Mount without writing in /etc/mtab. This is necessary for example when /etc is on a read-only filesystem.
Many more nuances are given in the manual page.
add a comment |
According to man mount
:
The programs mount and umount traditionally maintained a list of currently mounted filesystems in the file /etc/mtab. This real mtab file is still supported, but on current Linux systems it is better to make it a symlink to /proc/mounts instead, because a regular mtab file maintained in userspace cannot reliably work with namespaces, containers and other advanced Linux features.
On mounting without recording in /etc/mtab
:
-n, --no-mtab
Mount without writing in /etc/mtab. This is necessary for example when /etc is on a read-only filesystem.
Many more nuances are given in the manual page.
According to man mount
:
The programs mount and umount traditionally maintained a list of currently mounted filesystems in the file /etc/mtab. This real mtab file is still supported, but on current Linux systems it is better to make it a symlink to /proc/mounts instead, because a regular mtab file maintained in userspace cannot reliably work with namespaces, containers and other advanced Linux features.
On mounting without recording in /etc/mtab
:
-n, --no-mtab
Mount without writing in /etc/mtab. This is necessary for example when /etc is on a read-only filesystem.
Many more nuances are given in the manual page.
answered Apr 23 at 17:57
ChristopherChristopher
11k33350
11k33350
add a comment |
add a comment |
Sathish kumar is a new contributor. Be nice, and check out our Code of Conduct.
Sathish kumar is a new contributor. Be nice, and check out our Code of Conduct.
Sathish kumar is a new contributor. Be nice, and check out our Code of Conduct.
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Related: Is there a command to see where a disk is mounted?
– Kusalananda♦
Apr 23 at 17:35
I find it frustrating that
man 5 mtab
is missing.– Weijun Zhou
Apr 23 at 17:48
2
Also: unix.stackexchange.com/q/24182/117549
– Jeff Schaller♦
Apr 23 at 18:08