[Gluster-users] understanding dht value

Ankireddypalle Reddy
Tue, 08 Nov 2016 19:04:03 -0000

Hi,
       I am trying to make sense of the hash values that get assigned/used by
DHT.
       /brick1/vol and /brick2/vol are the directories that are being used as
bricks in a distributed  replicated volume.

[root at glusterhackervm3 glus]# getfattr  -n trusted.glusterfs.dht -e hex
/brick1/vol
getfattr: Removing leading '/' from absolute path names
# file: brick1/vol
trusted.glusterfs.dht=0x0000000100000000000000007ffffde1
This means that any file gets hashed to a value from 0x00 to 0x7ffffde1 gets
stored on this brick.


[root at glusterhackervm3 glus]# getfattr  -n trusted.glusterfs.dht -e hex
/brick2/vol
getfattr: Removing leading '/' from absolute path names
# file: brick2/vol
trusted.glusterfs.dht=0x00000001000000007ffffde2ffffffff
This means that any file that's hashed to a value from 0x7ffffde2 to
0xffffffff gets stored on this brick.


What is confusing is the dht values that are shown for the directories inside
these brick directories. What do the dht values associated with the sub
directories signify.

[root at glusterhackervm3 glus]# getfattr  -n trusted.glusterfs.dht -e hex
/brick2/vol/d/
getfattr: Removing leading '/' from absolute path names
# file: brick2/vol/d/
trusted.glusterfs.dht=0x0000000100000000000000007ffffffe

[root at glusterhackervm3 glus]# getfattr  -n trusted.glusterfs.dht -e hex
/brick2/vol/d/e
getfattr: Removing leading '/' from absolute path names
# file: brick2/vol/d/e
trusted.glusterfs.dht=0x0000000100000000000000007ffffffe


[root at glusterhackervm3 glus]# getfattr  -n trusted.glusterfs.dht -e hex
/brick2/vol/d/f
getfattr: Removing leading '/' from absolute path names
# file: brick2/vol/d/f
trusted.glusterfs.dht=0x00000001000000007fffffffffffffff

Thanks and Regards,
Ram
***************************Legal Disclaimer***************************
"This communication may contain confidential and privileged material for
the
sole use of the intended recipient. Any unauthorized review, use or distribution
by others is strictly prohibited. If you have received the message by mistake,
please advise the sender by reply email and delete the message. Thank you."
**********************************************************************
-------------- next part --------------
An HTML attachment was scrubbed...
URL:
<http://www.gluster.org/pipermail/gluster-users/attachments/20161108/080cd240/attachment.html>