Linux: Raspberry – Read Only Modus reparieren

Nach einem Stromausfall gab es beim Raspberry das Problem, das die / (root) Partition nur noch im Read Only Modus war. Wie man das wieder Rückgängig macht, erkläre ich hier.

Prüfen ob die Root Partion im Read Only Modus (ro) ist:

root@openHAB:~# mount
sysfs on /sys type sysfs (rw,nosuid,nodev,noexec,relatime)
proc on /proc type proc (rw,nosuid,nodev,noexec,relatime)
udev on /dev type devtmpfs (rw,nosuid,relatime,size=3725276k,nr_inodes=931319,mode=755)
devpts on /dev/pts type devpts (rw,nosuid,noexec,relatime,gid=5,mode=620,ptmxmode=000)
tmpfs on /run type tmpfs (rw,nosuid,nodev,noexec,relatime,size=799644k,mode=755)
/dev/sda2 on / type ext4 (ro,relatime)
securityfs on /sys/kernel/security type securityfs (rw,nosuid,nodev,noexec,relatime)
tmpfs on /dev/shm type tmpfs (rw,nosuid,nodev)
tmpfs on /run/lock type tmpfs (rw,nosuid,nodev,noexec,relatime,size=5120k)
cgroup2 on /sys/fs/cgroup type cgroup2 (rw,nosuid,nodev,noexec,relatime,nsdelegate,memory_recursiveprot)
pstore on /sys/fs/pstore type pstore (rw,nosuid,nodev,noexec,relatime)
bpf on /sys/fs/bpf type bpf (rw,nosuid,nodev,noexec,relatime,mode=700)
systemd-1 on /proc/sys/fs/binfmt_misc type autofs (rw,relatime,fd=29,pgrp=1,timeout=0,minproto=5,maxproto=5,direct,pipe_ino=2785)
mqueue on /dev/mqueue type mqueue (rw,nosuid,nodev,noexec,relatime)
debugfs on /sys/kernel/debug type debugfs (rw,nosuid,nodev,noexec,relatime)
tracefs on /sys/kernel/tracing type tracefs (rw,nosuid,nodev,noexec,relatime)
ramfs on /run/credentials/systemd-sysctl.service type ramfs (ro,nosuid,nodev,noexec,relatime,mode=700)
configfs on /sys/kernel/config type configfs (rw,nosuid,nodev,noexec,relatime)
fusectl on /sys/fs/fuse/connections type fusectl (rw,nosuid,nodev,noexec,relatime)
ramfs on /run/credentials/systemd-tmpfiles-setup-dev.service type ramfs (ro,nosuid,nodev,noexec,relatime,mode=700)
ramfs on /run/credentials/systemd-tmpfiles-setup.service type ramfs (ro,nosuid,nodev,noexec,relatime,mode=700)
binfmt_misc on /proc/sys/fs/binfmt_misc type binfmt_misc (rw,nosuid,nodev,noexec,relatime)
sunrpc on /run/rpc_pipefs type rpc_pipefs (rw,relatime)
tmpfs on /run/user/1000 type tmpfs (rw,nosuid,nodev,relatime,size=799644k,nr_inodes=199911,mode=700,uid=1000,gid=1000)
tmpfs on /run/user/106 type tmpfs (rw,nosuid,nodev,relatime,size=799644k,nr_inodes=199911,mode=700,uid=106,gid=111)
gvfsd-fuse on /run/user/106/gvfs type fuse.gvfsd-fuse (rw,nosuid,nodev,relatime,user_id=106,group_id=111)

Wenn ja, versuchen diese zu reparieren:

e2fsck -y /dev/sda2

Wenn ok und kein Fehler, die Root Partition wieder passend mounten:

mount -o remount,rw /dev/sda2 /

Prüfen ob die /etc/fstab Inhalt hat:

cat /etc/fstab

Bei mir war die leer, also entsprechende Infos einholen:

root@openHAB:~# blkid
/dev/sda2: LABEL="rootfs" UUID="fc7a1f9e-4967-4f41-a1f5-1b5927e6c5f9" BLOCK_SIZE="4096" TYPE="ext4" PARTUUID="4fb9849b-02"
/dev/sda1: LABEL_FATBOOT="bootfs" LABEL="bootfs" UUID="50C8-AEAE" BLOCK_SIZE="512" TYPE="vfat" PARTUUID="4fb9849b-01"

Die /etc/fstab Datei neu aufbauen:

proc            /proc           proc    defaults          0       0
PARTUUID=4fb9849b-01  /boot           vfat    defaults,flush    0       2
PARTUUID=4fb9849b-02  /               ext4    defaults,noatime  0       1

Server neu starten und prüfen ob die Root Partition weiterhin im Read Only Modus ist:

reboot

root@openHAB:~# mount
sysfs on /sys type sysfs (rw,nosuid,nodev,noexec,relatime)
proc on /proc type proc (rw,nosuid,nodev,noexec,relatime)
udev on /dev type devtmpfs (rw,nosuid,relatime,size=3725276k,nr_inodes=931319,mode=755)
devpts on /dev/pts type devpts (rw,nosuid,noexec,relatime,gid=5,mode=620,ptmxmode=000)
tmpfs on /run type tmpfs (rw,nosuid,nodev,noexec,relatime,size=799644k,mode=755)
/dev/sda2 on / type ext4 (rw,relatime)
securityfs on /sys/kernel/security type securityfs (rw,nosuid,nodev,noexec,relatime)
tmpfs on /dev/shm type tmpfs (rw,nosuid,nodev)
tmpfs on /run/lock type tmpfs (rw,nosuid,nodev,noexec,relatime,size=5120k)
cgroup2 on /sys/fs/cgroup type cgroup2 (rw,nosuid,nodev,noexec,relatime,nsdelegate,memory_recursiveprot)
pstore on /sys/fs/pstore type pstore (rw,nosuid,nodev,noexec,relatime)
bpf on /sys/fs/bpf type bpf (rw,nosuid,nodev,noexec,relatime,mode=700)
systemd-1 on /proc/sys/fs/binfmt_misc type autofs (rw,relatime,fd=29,pgrp=1,timeout=0,minproto=5,maxproto=5,direct,pipe_ino=2785)
mqueue on /dev/mqueue type mqueue (rw,nosuid,nodev,noexec,relatime)
debugfs on /sys/kernel/debug type debugfs (rw,nosuid,nodev,noexec,relatime)
tracefs on /sys/kernel/tracing type tracefs (rw,nosuid,nodev,noexec,relatime)
ramfs on /run/credentials/systemd-sysctl.service type ramfs (ro,nosuid,nodev,noexec,relatime,mode=700)
configfs on /sys/kernel/config type configfs (rw,nosuid,nodev,noexec,relatime)
fusectl on /sys/fs/fuse/connections type fusectl (rw,nosuid,nodev,noexec,relatime)
ramfs on /run/credentials/systemd-tmpfiles-setup-dev.service type ramfs (ro,nosuid,nodev,noexec,relatime,mode=700)
ramfs on /run/credentials/systemd-tmpfiles-setup.service type ramfs (ro,nosuid,nodev,noexec,relatime,mode=700)
binfmt_misc on /proc/sys/fs/binfmt_misc type binfmt_misc (rw,nosuid,nodev,noexec,relatime)
sunrpc on /run/rpc_pipefs type rpc_pipefs (rw,relatime)
tmpfs on /run/user/1000 type tmpfs (rw,nosuid,nodev,relatime,size=799644k,nr_inodes=199911,mode=700,uid=1000,gid=1000)
tmpfs on /run/user/106 type tmpfs (rw,nosuid,nodev,relatime,size=799644k,nr_inodes=199911,mode=700,uid=106,gid=111)
gvfsd-fuse on /run/user/106/gvfs type fuse.gvfsd-fuse (rw,nosuid,nodev,relatime,user_id=106,group_id=111)