During system startup, a Linux administrator sees the following on the console for roughly 90 seconds:
A start job is running for dev-disk-by\x2duuid-3d2e8f6f…device (1min 30s / no limit)
After the pause, the machine finishes booting and works normally. The same delay occurs on every reboot, and systemd-analyze critical-chain attributes the wait to the dev-disk-by-uuid-3d2e8f6f.device unit. Which corrective action is MOST likely to remove the long startup delay?
Disable udev persistent naming for block devices by removing /etc/udev/rules.d/70-persistent-disk.rules.
Update or comment out the stale UUID entry in /etc/fstab so it matches an existing block device.
Increase DefaultTimeoutStartSec in /etc/systemd/system.conf from 90 seconds to 180 seconds.
Rebuild the initramfs image to ensure the required storage driver loads earlier in the boot process.
The message shows that systemd is waiting for a block device with a specific UUID before continuing the boot. That device reference comes from /etc/fstab; if the UUID no longer exists (for example, a swap or data partition was deleted or its UUID changed), systemd waits 90 seconds for it to appear, causing the slow start.
Updating the UUID in /etc/fstab to match the actual device (or commenting out the stale line) stops systemd from looking for a non-existent device, eliminating the delay.
Rebuilding the initramfs only changes which kernel modules are pre-loaded; it does not correct an invalid mount entry, so the timeout would remain.
Increasing DefaultTimeoutStartSec merely lengthens the waiting period instead of fixing the root cause, making the boot even slower.
Disabling udev's persistent naming rules affects device names such as /dev/sda, not the UUID entries in /etc/fstab, so it would not resolve the issue.
Therefore, correcting or removing the wrong UUID in /etc/fstab is the effective fix.
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What is the function of `/etc/fstab` in Linux?
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