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| author | humblec <hchiramm@redhat.com> | 2015-08-19 12:44:30 +0530 |
|---|---|---|
| committer | humblec <hchiramm@redhat.com> | 2015-08-19 12:44:30 +0530 |
| commit | ab56824693543455974da00b45248f6d9a400d02 (patch) | |
| tree | 778c02c9f206c0ef2fffc42d3d4a7053d7860b79 /Features/worm.md | |
| parent | 84dd6aa9ab1ac1fe9e8e8afad0accadc0163b114 (diff) | |
| parent | 8787ab44dd9425ca173d8d24d8998334e9db23c2 (diff) | |
Merge branch 'github/master' into newlocal
Diffstat (limited to 'Features/worm.md')
| -rw-r--r-- | Features/worm.md | 75 |
1 files changed, 75 insertions, 0 deletions
diff --git a/Features/worm.md b/Features/worm.md new file mode 100644 index 0000000..dba9977 --- /dev/null +++ b/Features/worm.md @@ -0,0 +1,75 @@ +#WORM (Write Once Read Many) +This features enables you to create a `WORM volume` using gluster CLI. +##Description +WORM (write once,read many) is a desired feature for users who want to store data such as `log files` and where data is not allowed to get modified. + +GlusterFS provides a new key `features.worm` which takes boolean values(enable/disable) for volume set. + +Internally, the volume set command with 'feature.worm' key will add 'features/worm' translator in the brick's volume file. + +`This change would be reflected on a subsequent restart of the volume`, i.e gluster volume stop, followed by a gluster volume start. + +With a volume converted to WORM, the changes are as follows: + +* Reads are handled normally +* Only files with O_APPEND flag will be supported. +* Truncation,deletion wont be supported. + +##Volume Options +Use the volume set command on a volume and see if the volume is actually turned into WORM type. + + # features.worm enable +##Fully loaded Example +WORM feature is being supported from glusterfs version 3.4 +start glusterd by using the command + + # service glusterd start +Now create a volume by using the command + + # gluster volume create <vol_name> <brick_path> +start the volume created by running the command below. + + # gluster vol start <vol_name> +Run the command below to make sure that volume is created. + + # gluster volume info +Now turn on the WORM feature on the volume by using the command + + # gluster vol set <vol_name> worm enable +Verify that the option is set by using the command + + # gluster volume info +User should be able to see another option in the volume info + + # features.worm: enable +Now restart the volume for the changes to reflect, by performing volume stop and start. + + # gluster volume <vol_name> stop + # gluster volume <vol_name> start +Now mount the volume using fuse mount + + # mount -t glusterfs <vol_name> <mnt_point> +create a file inside the mount point by running the command below + + # touch <file_name> +Verify that user is able to create a file by running the command below + + # ls <file_name> + +##How To Test +Now try deleting the above file which is been created + + # rm <file_name> +Since WORM is enabled on the volume, it gives the following error message `rm: cannot remove '/<mnt_point>/<file_name>': Read-only file system` + +put some content into the file which is created above. + + # echo "at the end of the file" >> <file_name> +Now try editing the file by running the commnad below and verify that the following error message is displayed `rm: cannot remove '/<mnt_point>/<file_name>': Read-only file system` + + # sed -i "1iAt the beginning of the file" <file_name> +Now read the contents of the file and verify that file can be read. + + cat <file_name> + +`Note: If WORM option is set on the volume before it is started, then volume need not be restarted for the changes to get reflected`. |
