[openduckbill commit] r36 - wiki
codesite...@google.com
Date: Thu Feb 21 01:38:11 2008
New Revision: 36
Modified:
wiki/OpenduckbillReadme.wiki
Log:
Edited wiki page through web user interface.
Modified: wiki/OpenduckbillReadme.wiki
==============================================================================
--- wiki/OpenduckbillReadme.wiki (original)
+++ wiki/OpenduckbillReadme.wiki Thu Feb 21 01:38:11 2008
@@ -52,16 +52,20 @@
* mount/umount commands
* Root privileges during installation
+ _Also see section "Server Requirements"_
+
= Installation =
Copy the openduckbill archive into a temporary directory
{{{
$ cp openduckbill-1.0.0.tar.gz /tmp/
+ # cp openduckbill-1.0.0.tar.bz2 /tmp/
}}}
Untar the archive
{{{
$ cd /tmp
$ tar -xzvf openduckbill-1.0.0.tar.gz
+ # tar -xjvf openduckbill-1.0.0.tar.bz2
$ cd openduckbill-1.0.0
}}}
Installation is made simple by the bash script `install.sh`. The
script takes an argument, which is the directory where openduckbill
needs to be installed.
@@ -315,7 +319,7 @@
localmount : "/mnt/odb_mount"
nfsmountoptions : "rw,nosuid,soft"
}}}
- If RSYNC is selected as backup method, "method" section "RSYNC" need
to available. For example:
+ If RSYNC is selected as backup method, "method" section "RSYNC" need
to be available. For example:
{{{
RSYNC :
server : "server2.mydomain.com"
@@ -420,6 +424,7 @@
= A Note on backup version support =
Openduckbill always tries to maintain an exact copy of data marked
for backup. There is no true (see below paragraph) version support
built into openduckbill (is another TODO). So if data has changed at
source and this needs to be recovered from openduckbill backup
destination, it is not possible to get the old file, if openduckbill
has already synced the changes to the backup destination. This can
happen, when "syncinterval" is low and by the time, the files are
checked out from the backup destination, it might already have been
overwritten with a new copy by openduckbill. In such a scenario,
openduckbill "syncinterval" could be increased to a higher value like
say 1 hour (3600 seconds). Adjust the "commitchanges" value depending
on the filesystem activity (Default should be still fine).
+
Another means to enable version support in openduckbill is by
enabling the parameter "maintainprevious". Once enabled, openduckbill
will also keep a copy of the old file in the backup destination, in
addition to the new modified file. The old file is kept with a file
extention ".odb~". This parameter thus brings current and previous file
version support to openduckbill. Enabling this option, will also
increase disk usage considerably at the remote backup destination. Have
a look at the notes on "maintainprevious" in *Understanding the config file*.
= Setting up passwordless ssh =
@@ -441,15 +446,50 @@
Openduckbill prints debug messages to the console as well as the log
file (~/.openduckbill/messages.log).
-= Uninstall =
+= Server Requirements =
- For uninstalling, all that needs to be done is remove the directory
which holds the openduckbill python code. Assuming it was installed in `/usr/local/openduckbill`
+ There is little or no configuration required at the server (NFS |
SSH) side for openduckbill. As mentioned earlier the openduckbill will
be able to perform backup to NFS or SSH (backupmethod : RSYNC) servers.
The only requirement for openduckbill, for using the NFS or SSH server,
is that the remote directory where data has to be dumped to, should
have read and write permission for the user running openduckbill.
+
+ For "backupmethod" as RSYNC, passwordless ssh needs to be
configured, else openduckbill will need to be supplied with password of
the user, every time a backup is attempted. Check the
[http://code.google.com/p/openduckbill/wiki/OpenduckbillAccessControl
access control] docs on how to set this up.
+
+ For "backupmethod" as NFS, the NFS mount should be writable and
mountable at the local box. Also an entry need to be added to
`/etc/fstab` which allows, the user running openduckbill to mount the
NFS export at the local machine. (Also mentioned in "NFS method"
section of *Understanding the Config File*)
+
+= Performance =
+
+ Openduckbill uses rsync in the background for transferring data.
Rsync is a very powerful tool for doing data transfer. However, the
transfer rate largely depends on the network bandwidth available. For
obvious reasons, LOCAL backup would be faster. NFS, RSYNC backup would
depend on the network latency between the local box and the remote
servers (NFS | SSH).
+
+= Security =
+
+ On the remote server (NFS | SSH), openduckbill creates a backup
directory path of following format, where "/tmp/odb" is the remotemount
parameter mentioned in the `config.yaml`
{{{
- $ ps -ef | grep openduckbill
- $ kill -9 <pid of openduckbill>
- $ rm -rvi /usr/local/openduckbill/
+ /tmp/odb/<username>/__backups__/<hostname>
}}}
- The config and log files are in `~/.openduckbill/`, which can be removed.
+ The permissions on the directory /tmp/odb/<username> is 0700. This
is done by openduckbill (using chmod) during the directory creation
time (first run). Only the user owning the directory and the super-user
will have permissions to access the backup directory.
+
+ Note: Any access permissions which apply on the server will be
applicable to the openduckbill backup path as well.
+
+ Since the only owner of the directory can access the path, multiple
users can run openduckbill and can use the same location ("/tmp/odb" in
this case) for keeping the backup data.
+{{{
+ /tmp/odb/user1/__backups__/some_random_host/...
+ /tmp/odb/user2/__backups__/some_random_host/...
+ /tmp/odb/user3/__backups__/some_random_host/...
+ /tmp/odb/user4/__backups__/some_random_host/...
+}}}
+
+ If an user is running openduckbill from multiple hosts, the backup
path would be as below:
+{{{
+ /tmp/odb/user1/__backups__/some_random_host_1/...
+ /tmp/odb/user1/__backups__/some_random_host_2/...
+ /tmp/odb/user1/__backups__/some_random_host_3/...
+ /tmp/odb/user2/__backups__/some_random_host/...
+ /tmp/odb/user3/__backups__/some_random_host/...
+ /tmp/odb/user4/__backups__/some_random_host/...
+}}}
+
+= Caveats =
+
+ * Backup path on the remote server is created depending on the
hostname (short hostname) of local machine. If there are hosts with
same name, and user tries to run backup from these, chances of possible
data corruption is high.
+ * The data placed at the remote end is not encrypted and is stored
as regular files/directories (as it was at the source). Openduckbill
makes sure, the directory where the data is placed is accessible only
to the user running openduckbill. However, if super-user cannot be
trusted in the remote system, dumping data to remote is not recommended.
= TODO =
@@ -459,7 +499,8 @@
* Add better file version support (instead of rsync's backup feature)
* Support compression at remote end.
* Ability to check backup destination disk space/quota.
- * Read config during runtime.
+ * Re-read config during runtime.
+ * Data dumped to the remote, to be encrypted by some secure means.
= Troubleshooting =
@@ -541,11 +582,29 @@
If you find openduckbill waiting at password prompt, when backup
method is selected as RSYNC. The please refer *Setting up passwordless ssh*
+=== Daemon mode error logging ===
+
+ In the daemon mode, openduckbill prints only messages of level
warning and above to cnosole (even in debug mode). So if backups fail
or openduckbill aborts execution, check the log file
`~/.openduckbill/messages.log` for more detailed messages.
+
+=== Log file size ===
+
+ All log messages are sent to `~/.openduckbill/messages.log` and over
time, the size of the file can increase. It is safe to truncate the
file using the command `echo > messages.log`
+
_Add more to this section_
= Platforms =
Openduckbill has been tested to work on x86 Linux (Fedora 6, Ubuntu Dapper/Gutsy).
+
+= Uninstall =
+
+ For uninstalling, all that needs to be done is remove the directory
which holds the openduckbill python code. Assuming it was installed in `/usr/local/openduckbill`
+{{{
+ $ ps -ef | grep openduckbill
+ $ kill -9 <pid of openduckbill>
+ $ rm -rvi /usr/local/openduckbill/
+}}}
+ The config and log files are in `~/.openduckbill/`, which can be removed.
= About =