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Show the UUID-based alternate device names of ZEVO-related partitions on Darwin/OS X. Adapted from the lines by dbrady at http://zevo.getgreenbytes.com/forum/viewtopic.php?p=700#p700 and following the disk device naming scheme at http://zevo.getgreenbytes.com/wiki/pmwiki.php?n=Site.DiskDeviceNames
Shows all block devices in a tree with descruptions of what they are.
`blkid` is an interface to libuuid - it can read Device Mapper, EVMS, LVM, MD, and regular block devices.
-c /dev/null - Do not use cached output from /etc/blkid.tab or /etc/blkid/blkid.tab (RHEL)
-i - Display I/O Limits (aka I/O topology) information (not available in RHEL)
-p - Low-level superblock probing mode (not available in RHEL)
Remove the dashes from a UUID using bash search and replace.
Shows the UUID of the given partition (here /dev/sda7). Doesn't need to be root.
first off, if you just want a random UUID, here's the actual command to use:
Your chances of finding a duplicate after running this nonstop for a year are about the same as being hit by a meteorite before finishing this sentence
The reason for the command I have is that it's more provably unique than the one that uuidgen creates. uuidgen creates a random one by default, or an unencrypted one based on time and network address if you give it the -t option.
Mine uses the mac address of the ethernet interface, the process id of the caller, and the system time down to nanosecond resolution, which is provably unique over all computers past, present, and future, subject to collisions in the cryptographic hash used, and the uniqueness of your mac address.
Warning: feel free to experiment, but be warned that the stdin of the hash is binary data at that point, which may mess up your terminal if you don't pipe it into something. If it does mess up though, just type