Difference between SATA I, SATA II and SATA III

What is the difference between SATA I, SATA II and SATA III? SATA I (revision 1.x) interface, formally known as SATA 1.5Gb/s, is the first generation SATA interface running at 1.5 Gb/s. The bandwidth throughput, which is supported by the interface, is up to 150MB/s. SATA II (revision 2.x) interface, formally known as SATA 3Gb/s, Read more about Difference between SATA I, SATA II and SATA III[…]

Smartctl on Linux

SMART (Self-Monitoring, Analysis, and Reporting Technology) allows you to see the status or overall health of a hard drive. This information is instumental in providing warning signs of problems with a hard drive. All Linux distributions provide the smartmontools package, which contain the smartctl program used to display SMART information from attached drives. This package Read more about Smartctl on Linux[…]

PHP Sessions causing Error

Currently your messages log is filling up with errors and the system is unstable. Check the message log: $ server# tail -f /var/log/messages Jul 28 08:57:30 mail kernel: EXT4-fs warning (device sda3): ext4_dx_add_entry: Directory index full! Check the sessions directory $ server# php -i | grep session.save_path session.save_path => /var/lib/php/session => /var/lib/php/session $ server# du Read more about PHP Sessions causing Error[…]

Check disk IO

To check disk IO: dd bs=1M count=512 if=/dev/zero of=test conv=fdatasync 512+0 records in 512+0 records out 536870912 bytes (537 MB) copied, 5.57475 s, 96.3 MB/s

Hard Drive Tools

With respect to hard drives, the acronym “SMART” stands for Self-Monitoring, Analysis and Reporting Technology. This was built into many ATA-3 and later ATA, IDE and SCSI-3 hard drives. Basically anything after about 2005 should have it. Ubuntu/Debian: sudo apt-get install smartmontools CentOS/Fedora/RH: sudo yum install smartmontools Gentoo: sudo emerge sys-apps/smartmontools Wiki: http://sourceforge.net/apps/trac/smartmontools/wiki smartctl The Read more about Hard Drive Tools[…]