Tipsheet

Godaddys' linux hosting allows for editing your own "php.ini" file and enables support for logging errors, good for debugging purposes when developing with php.

Add the below lines to php.ini in the document root, to log all errors:

You should also protect the php.ini and error_log file via .htaccess:

If using earlier versions, use "star" to backup and restore files with extended attributes. SELinux and ACLs use these Extended Attributes to store the security contexts and access control lists respectively.

Tar has now been rebuilt in RedHat 5 and added support for Extended Attributes.

--selinux Archive the SELinux attributes of the files and directories
--acls Archive the ACL attributes of files and directories
--xattrs Archive all Extended Attributes of files and directories.
This includes both SELinux and ACL attributes, as well as any other xattr.

setuid files when executed inherit the permissions of the owner of the file. So having files with setuid of root is a bad idea.

Here's how to find it and unset it.

Note:
There are some system files like at and crontab that have these bits set and is required for it to run.

To unset it:

Edit "/etc/yum/pluginconf.d/installonlyn.conf" and change the enabled to "0" or increase the "tokeep" value to the number of versions you want to keep.

Place the snippet of code in an index.php file to pull up a different web page for each domain pointed to the same web-space.

Allows for easy sharing of internet connection to an internal network with dynamic IP range.

1. Create RAID-1 level array with 2 active devices and 1 spare:
   
   # mdadm -C /dev/md0 -l 1 -n 2 /dev/hda{8,9} -x 1 /dev/hda10

   Note: RAID-1 provides for redundancy and needs a minimum of 2 partitions and any number of spares.

2. Show details:
   
   # mdadm --detail /dev/md0
3. Mark Faulty:
   
   # mdadm --manage /dev/md0 -f /dev/hda8

   Note: When partition is marked faulty, the spare quickly replaces it in RAID 1 array.

4. Remove:
   
   # mdadm --manage /dev/md0 -r /dev/hda8

   Note: Only faulty partitions can be removed.

5. Add:
   
   # mdadm --manage /dev/md0 -a /dev/hda8

   Note: Only removed partitions can be added.

6. Stop RAID:
   
   # mdadm --stop /dev/md0
7. Run RAID:
   
   # mdadm --assemble /dev/md0 /dev/hda{8,9,10}

   Note: Before assembling, check on the UUID of the devices. They should all be the same and show only one array:
   

   mdadm --examine --scan /dev/hda{8,9,10}

8. Remove the md signature from disk
   
   # mdadm --zero-superblock /dev/hda{8,9,10}
9. Scan md superblock
   
   # mdadm --examine --scan
10. Scan currently active arrays
    
    mdadm --detail --scan
11. Monitor RAID:
    
    # nohup mdadm --monitor --mail=root --delay=300 /dev/md0 &

You might come across a disc image in the BIN/CUE format. BIN/CUE files can be directly burned to CD via K3B, however if you want to convert to an iso, a command line application called bchunk can be used.

Check to make sure the quota package is installed, else run: