Tuning and debugging filesystems

Three tools are particularly important: dumpe2fs, tune2fs and debugfs. dumpe2fs shows info about ext2 and ext3 partitions. It can be safely run on a filesystem that’s currently mounted: dumpe2fs [options] [device] -h omits info about group descriptors, useful for advanced debugging. Inode count it’s the number of inodes supported by the filesystem. Every inode contains… Continue reading “Tuning and debugging filesystems”

Common partitions and filesystem layout

swap not mounted, 1-2 times the RAM size /home holds users’ data files /boot holds critical boot files /usr holds most Linux program data files /usr/local holds Linux program and data files that are unique to the current installation /opt third part packages /var misc files associated with day-to-day tasks /tmp temporary files created by… Continue reading “Common partitions and filesystem layout”

Linux partitioning system

MBR was the most used until 2010, it stores data in the first sector of the disk and it’s limited to 2TiB partitions. GPT (GUID Partition Table) has much higher limits. MBR partitions The original x86 allowed only four partitions, but this scheme was extended. The new scheme uses three partition types: primary partitions extended… Continue reading “Linux partitioning system”