Category: System (系统)

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[DEBUG] Linux resolve df command is stuck

Error phenomenon:

Input df command and the command is stuck
Can not us cd / command to access /(root) directory
Can not us ls / command to display /(root) directory

Analysis:

There may be some network storage disconnected

Solution:

Step One: Use mount command to check if there is any disconnected network storage here

# mount

(Add: At this moment, we can see at least one remote storage mount to local directory. If we cd to this directory, system command prompt will output target is busy)

Step Two: Use unmount command to unmount this disconnected network storage

# umount -f <nfs storage which is stuck>

Or:

# umount -l <nfs storage which is stuck>

Or:

# umount -f -l <nfs storage which is stuck>
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[CONTENT] Linux recommended swap size

Content:

For RHEL 6, RHEL 7, RHEL 8, RHEL 9

RAM sizeRecommended swap sizeRecommended swap size if allowing for hibernation
From 0 to 2GB 2 times the RAM size3 times the RAM size
From 2GB to 8GBThe same size of the RAM2 times the RAM size
From 8GB to 64GBAt least 4GB1.5 times the RAM size
From 64GBAt least 4GBHibernation is not recommended
RHEL 6, RHEL 7, RHEL 8, RHEL 9 Recommended Swap Size Table

Note: A 100GB swap is recommended if system with over 140 logical processes or over 3TB RAM

Reference:

https://access.redhat.com/solutions/15244