Disk¶

show disk usage¶

df -h
du -sh ./*  #total
du -ahd1 . | sort -rh # `-a` include hidden files, `-d1` only prints data up to the first hierarchie level

check hard disk health¶

install sudo apt install smartmontools

lsblk #list all hard drives, or use sudo fdisk -l
lsblk -o NAME,MODEL,SIZE,TYPE #list type as well
df /home/user/Documents #find the disk the folder belongs to
sudo smartctl -a /dev/sda #check disk health

file-system became read-only¶

A common reason for a file-system to be read-only is because it has errors, and needs fsck (file system check).

mount | grep sda1

sudo fsck -Af -M
sudo fsck.ext4 -f /dev/sda1 #if the file system is ext4
sudo reboot

/var/lib/docker: Device or resource busy¶

When run rm -rf /var/lib/docker or umount /dev/xxx got the error. Possible reason: still in the mounted device.

mount help¶

man mount.cifs

unmount cifs¶

umount -a -t cifs -l    # umount all cifs
umount /mnt/cifs_share  # umount a specific cifs

mount cifs network drive¶

https://linuxize.com/post/how-to-mount-cifs-windows-share-on-linux/
https://unix.stackexchange.com/questions/68079/mount-cifs-network-drive-write-permissions-and-chown

On Linux and UNIX operating systems, a Windows share can be mounted on a particular mount point in the local directory tree using the cifs option of the mount command.

The Common Internet File System (CIFS) is a network file-sharing protocol. CIFS is a form of SMB.

sudo mkdir /mnt/dat
sudo mount -t cifs -o username=${USER},password=${PASSWORD},uid=$(id -u),gid=$(id -g) //server-address/folder /mnt/dat
sudo mount -t cifs -o credentials=/etc/smb.credentials //server-address/folder /mnt/dat
sudo mount -t cifs //my-drive/dev /mnt/dev -o uid=1000,gid=1000,vers=3.0,defaults,credentials=/home/user/smb.credentials --verbose

To ensure the mount persists on system reboots, this command must be added to the fstab or equivalent to mount the DOCS DATA and VIEWER DATA on system startup.

# <file system>          <dir>    <type> <options>                                                   <dump>  <pass>
//server-address/folder  /mnt/dat  cifs  file_mode=0755,dir_mode=0755,credentials=/etc/win-credentials 0       0

# dat mount directory
//xyz1wes01/dat  /mnt/dat  cifs  uid=1000,gid=1000,vers=1.0,defaults,credentials=/home/user/smb.credentials 0 0

Run the following command to mount/umount the share:

sudo mount /mnt/dat
sudo umount /mnt/dat

where a path is mounted from¶

findmnt --target /etc/fstab # show mounted path
sudo cat /etc/fstab         # check the file content
mountpoint /mnt/myfolder    # will also tell if not mounted

mounted path is `ro` or `rw`¶

cat /proc/mounts
//xyz1wes01/dat /mnt/dat cifs rw,relatime,vers=1.0,cache=strict,username=usr,domain=,uid=1000,forceuid,gid=1000,forcegid,
addr=90.800.70.60,file_mode=0755,dir_mode=0755,soft,nounix,mapposix,rsize=61440,wsize=65536,echo_interval=60,actimeo=1 0 0

cifs logs¶

https://community.microfocus.com/img/oes/w/tips/14583/cifs-writing-in-2-differents-log-file

/var/log/messages
/var/log/cifs/cifs.log
/etc/rsyslog.d/cifs-log.conf

cifs troubleshooting¶

https://wiki.samba.org/index.php/LinuxCIFS_troubleshooting

debug data: /proc/fs/cifs/DebugData
debug message: dmesg

enalbe/disable debug

echo 7 | sudo tee /proc/fs/cifs/cifsFYI #enable debug
dmesg                                   #check log
echo 0 | sudo tee /proc/fs/cifs/cifsFYI #disable debug

check cifs client package: dpkg -l | grep cifs-utils
check cifs kernel module: lsmod | grep cifs
list all services: systemctl list-units

check mounted drive¶

To verify that the remote Windows share is successfully mounted, use either the mount or df -h command.

Can also check the network using ping <cifs_server_ip_or_hostname>

cifs issue¶

cifs mount suddenly no longer works¶

https://ubuntuforums.org/showthread.php?t=2490382

nodfs: disable dfs on the client side - for latest new Linux kernels on the client machine

sudo mount -t cifs //192.168.1.16/user /media/cloudbox -o username=user,password=xxx,vers=1.0,nodfs

CIFS VFS: Server has not responded¶

https://forums.linuxmint.com/viewtopic.php?t=190961

Solution:

Auto Mounting Samba Shares Using AutoFS: http://forums.linuxmint.com/viewtopic.php?f=42&t=144997
AutoFS is an "automounter" which means it doesn't mount at boot or login it only mounts when the mount point is accessed.
It also unmounts by itself when the share is not being used.

access cifs via smbclient¶

https://unix.stackexchange.com/questions/706325/smbclient-works-but-mount-cifs-doesnt-nt-status-more-processing-required

smbclient '\\172.25.162.14\nda20' -N -m NT1 --option="client min protocol"=NT1
mount -t cifs -vvvv //172.25.162.14/nda20 /mnt/aa -o username=root,vers=1.0,guest

smb error class and code¶

https://learn.microsoft.com/en-us/openspecs/windows_protocols/ms-cifs/8f11e0f3-d545-46cc-97e6-f00569e3e1bc