This command will mount all not-yet-mounted filesystems mentioned in fstab and is used in system script startup during booting. The mount command take an --fake or -f for short. The following command should do what you need:.
Introduction to fstab
This option is useful in conjunction with the -v flag to determine what the mount command is trying to do. Note this is Linux - check before using elsewhere: FreeBSD uses -f for 'force' - exactly the opposite meaning. That can be much more difficult to deal with if you have a headless box. Note that if you add a swap file to your fstab, mount -a won't turn it on: you'll want to run swapon -a.
Sign up to join this community. The best answers are voted up and rise to the top. Home Questions Tags Users Unanswered. How do you validate fstab without rebooting? Ask Question. Asked 9 years, 7 months ago. Active 8 months ago. Viewed 90k times. I verified the new devices and I can mount them with the mount command.
Luc M Luc M 2, 4 4 gold badges 22 22 silver badges 27 27 bronze badges. Active Oldest Votes. You can simple run: mount -a -a Mount all filesystems of the given types mentioned in fstab. Prix Prix 3, 3 3 gold badges 20 20 silver badges 21 21 bronze badges.
Also the fake option does not check whether the directory exists. This seems to be a good first thing to try, but you should also do a "mount -a" afterwards to verify.
In my case, I set the options to "default" instead of "defaults" which was preventing my Pi from bootingbut mount -fav validated it as correct. As soon as I did a mount -a it found an error. Vikas Avnish Vikas Avnish 1 1 bronze badge. Ian Hunter Ian Hunter 1 1 silver badge 11 11 bronze badges. TBH even fake mounting doesn't safely validate the fstab for bad fs type entries.In a nutshell, mounting is the process where a raw physical partition is prepared for access and assigned a location on the file system tree or mount point.
Options for mount and fstab are similar. Partitions listed in fstab can be configured to automatically mount during the boot process. Mount points should not have spaces in the names.
This field is usually set to 0, which disables it. The root device should be 1. Other partitions should be 2, or 0 to disable checking. Please refer to the examples section for sample entries. You may use any name you wish for the mount point, but you must create the mount point before you mount the partition. Auto will attempt to automatically detect the file system of the target file system and in general works well.
In general auto is used for removable devices and a specific file system or network protocol for network shares. Examples: auto vfat - used for FAT partitions. Options Options are dependent on the file system. You may use "defaults" here and some typical options may include : Ubuntu 8. This relates to when and how often the last access time of the current version of a file is updated, i.
It only takes a minute to sign up. When I did mount -ait asked user password to mount network share. It seems that it cannot proceed without password on boot, so it is just hung. According to the manpage mount. But it might be different on your system, better check your manpage for the correct argument names.
The other easy way is booting to live-cd mode and mount the right partition. Then you can fix anything you want! I found a solution to systems error kernel not loading Use live cd to gain access to your existing installation. Once in reinstall Linux kernel :.
Troubleshoot Linux VM starting issues due to fstab errors
May be I am too late. But this is FYI. In this situation you can use nano to load fstab and you can restart after editing the fstab. Sign up to join this community. The best answers are voted up and rise to the top. Home Questions Tags Users Unanswered. How to fix boot failure due to incorrect fstab? Ask Question.
Asked 7 years, 8 months ago. Active 1 year, 7 months ago. Viewed k times. How can I fix fstab to prevent boot failure? Pro Backup 3, 9 9 gold badges 39 39 silver badges 67 67 bronze badges. Active Oldest Votes. This is still true today - over six years later.
Saved my life. Good answer.
How to Fix “failed to mount /etc/fstab” Error in Linux
I was about to create snapshot, but while I was experimenting with fstabvm instance went off for some reason. Apparently, I wouldn't ask the question if I could fix it myself. Your problem description is a little bit unclear.
It should only try to mount the root fs and leave the fstab alone. Archemar Jp Jp 11 2 2 bronze badges. Choxmi Choxmi 2 2 bronze badges. Sign up or log in Sign up using Google. Sign up using Facebook. Sign up using Email and Password. Post as a guest Name. Email Required, but never shown.In this mode the only drive root is mounted as read-only.How To Automatically Mount Drives On Linux
Remember that the mount point must already exist, otherwise the entry will not mount on the filesystem. There can be other reasons. Some useful information can be recovered from dmesg. The dmesg command is used to write the kernel messages in Linux and other Unix-like operating systems to standard output which by default is the display screen. A kernel is the core of an operating system. It is the first part of the operating system that is loaded into memory when a computer boots up i.
The numerous messages generated by the kernel that appear on the display screen as a computer boots up show the hardware devices that the kernel detects and indicate whether it is able to configure them.
A buffer is a portion of a computer's memory that is set aside as a temporary holding place for data that is being sent to or received from an external device, such as a hard disk drive HDDprinter or keyboard. A ring buffer is a buffer of fixed size for which any new data added to it overwrites the oldest data in it. Its basic syntax is.
Invoking dmesg without any of its options which are rarely used causes it to write all the kernel messages to standard output. This usually produces far too many lines to fit into the display screen all at once, and thus only the final messages are visible. However, the output can be redirected to the less command through the use of a pipe designated by the vertical bar characterthereby allowing the startup messages to be viewed one screenful at a time:.
The more command could have been used here instead of the less command; however, less is newer than more and has additional functions, including the ability to return to previous pages of the output.
When a user encounters a problem with the system, it can be convenient to write the output of dmesg to a file and then send that file by e-mail to a system administrator or other knowledgeable person for assistance. Because of the length of the output of dmesg, it can be convenient to pipe its output to grepa filter which searches for any lines that contain the string i.
The -i option can be used to tell grep to ignore the case i. For example, the following command lists all references to USB universal serial bus devices in the kernel messages:. And the following tells dmesg to show all serial ports which are represented by the string tty :.
Whether or not 'defaults' are used in your setup are not necessarily relevant. Yes, you can expect 'defaults' here, but the lack therein doesn't hurt you a ton.
Troubleshooting Errors in /etc/fstab
As a security person, though, my advice is that if you believe your system was tampered with during installation outside that of the typical installer, then you should not be using that system, and should install with a known, good ISO and no networking during that installation to rule out network boot installer images causing issues.
This field is used by dump 8 to determine which filesystems need to be dumped. Defaults to zero don't dump if not present. This field is used by fsck 8 to determine the order in which filesystem checks are done at boot time. Filesystems within a drive will be checked sequentially, but filesystems on different drives will be checked at the same time to utilize parallelism available in the hardware.
Defaults to zero don't fsck if not present. It means that if any errors occur when trying to mount the device, it will be remount as read-only. Ubuntu Community Ask! Sign up to join this community. The best answers are voted up and rise to the top. Home Questions Tags Users Unanswered.
Ask Question. Asked 4 years, 4 months ago. Active 1 year, 7 months ago. Viewed 59k times. So what does this mean? Alice Alice 1 1 gold badge 1 1 silver badge 7 7 bronze badges.When you run the Boot Diagnostics feature on the Azure portalyou see log entries that resemble the following examples:.
To resolve this problem, start the VM in emergency mode by using the serial console for Azure Virtual Machines. Then use the tool to repair the file system.
Connect to the serial console. Use serial console to take single user mode single user mode. Once the vm has booted into single user mode. Use your favorite text editor to open the fstab file. Review the listed file systems. Each line in the fstab file indicates a file system that is mounted when the VM starts. For more information about the syntax of the fstab file, run the man fstab command.
To troubleshoot a start failure, review each line to make sure that it's correct in both structure and content. Change or comment out any incorrect or unnecessary lines in the fstab file to enable the VM to start correctly. Look for the error that indicates that the disk wasn't mounted. In the following example, the system was trying to attach a disk that was no longer present:. After the disk is mounted, run the following command for Nano:.
If the entries comment or fix was successful, the system should reach a bash prompt in the portal. Check whether you can connect to the VM.
Check your mount points when you test any fstab change by running the mount —a command. If there are no errors, your mount points should be good.
After you mount the system disk as a data disk on the recovery VM, back up the fstab file before you make changes, and then follow the next steps to correct the fstab file.
Look for the error that indicates the disk wasn't mounted. After the disk is mounted, run the following command for Nano.
Make sure that you're working on the fstab file that is located on the mounted disk and not the fstab file that's on the rescue VM. Unmount and detach the original virtual hard disk, and then create a VM from the original system disk.
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Server Fault is a question and answer site for system and network administrators. It only takes a minute to sign up. After a reboot, some partitions which were mentioned in fstab were not mounted as expected. The format of the line for the partitions which were mounted correctly and those which were not mounted correctly look the same so I am wondering whether some log exists of any problems which prevented the restoration of the missing partitions.
I am not able to see the console during a reboot but need to determine and fix the problem later. Note that some mount services such as s3 fuse require networking services to be enabled prior to the mount happening, so you may need to create an init.
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Asked 8 years, 1 month ago. Active 2 years, 1 month ago. Viewed 20k times. Stuart Woodward Stuart Woodward 1, 4 4 gold badges 14 14 silver badges 28 28 bronze badges.
Active Oldest Votes. There's a few things you could try: Assuming that they are still not mounted when you can login, does a mount -a cause any errors to get printed to your terminal? This will only use information available in the fstab to mount all available mounts, and should provide details of any mounts that are still failing to succeed. If you get no errors, and still have no mounts, are you sure that you don't have the noauto option enabled?
If you get no errors and now have mounts, perhaps there's some segregated mounting happening in your boot sequence and not all of those boot steps are enabled; eg, Gentoo has localmount and netmount and nfsmount init scripts for mounting things at boot. Is it an ordering issue? You can use the first numeric parameter in the fstab to control which mounts get mounted first. Failing any of the above, you can try going log diving. Your boot sequence should be being logged by default, but because it's dependant on your system logger's configuration it can change a little, even on different versions of the same distribution.
Matthew Scharley Matthew Scharley 1, 2 2 gold badges 13 13 silver badges 19 19 bronze badges. Sign up or log in Sign up using Google. Sign up using Facebook. Sign up using Email and Password. Post as a guest Name. Email Required, but never shown. The Overflow Blog. Featured on Meta. Feedback on Q2 Community Roadmap. Related 2.