The branch, master has been updated
via 3db8b1d7425ed5bd41e58b43c55fdac517d71baf (commit)
from 5334e40978350b6b597ee020bac52e37c8f9a8ba (commit)
http://gitweb.samba.org/?p=sahlberg/ctdb.git;a=shortlog;h=master
- Log -----------------------------------------------------------------
commit 3db8b1d7425ed5bd41e58b43c55fdac517d71baf
Author: Ronnie Sahlberg <[email protected]>
Date: Thu Jun 25 14:45:57 2009 +1000
update the man pages with the "getreclock" and "setreclock" commands.
-----------------------------------------------------------------------
Summary of changes:
doc/ctdb.1 | 23 ++++++++++++++-
doc/ctdb.1.html | 82 +++++++++++++++++++++++++++++++-----------------------
doc/ctdb.1.xml | 30 +++++++++++++++++++
doc/ctdbd.1 | 8 +++--
doc/ctdbd.1.html | 73 +++++++++++++++++++++++++----------------------
doc/ctdbd.1.xml | 8 ++++-
6 files changed, 149 insertions(+), 75 deletions(-)
Changeset truncated at 500 lines:
diff --git a/doc/ctdb.1 b/doc/ctdb.1
index 56b2353..5e451e9 100644
--- a/doc/ctdb.1
+++ b/doc/ctdb.1
@@ -1,11 +1,11 @@
.\" Title: ctdb
.\" Author:
.\" Generator: DocBook XSL Stylesheets v1.73.2 <http://docbook.sf.net/>
-.\" Date: 06/02/2009
+.\" Date: 06/25/2009
.\" Manual:
.\" Source:
.\"
-.TH "CTDB" "1" "06/02/2009" "" ""
+.TH "CTDB" "1" "06/25/2009" "" ""
.\" disable hyphenation
.nh
.\" disable justification (adjust text to left margin only)
@@ -403,6 +403,25 @@ CTDB version 1
This command is used to clear all statistics counters in a node\.
.PP
Example: ctdb statisticsreset
+.SS "getreclock"
+.PP
+This command is used to show the filename of the reclock file that is used\.
+.PP
+Example output:
+.sp
+.RS 4
+.nf
+Reclock file:/gpfs/\.ctdb/shared
+
+.fi
+.RE
+.SS "setreclock [filename]"
+.PP
+This command is used to modify, or clear, the file that is used as the reclock
file at runtime\. When this command is used, the reclock file checks are
disabled\. To re\-enable the checks the administrator needs to activate the
"VerifyRecoveryLock" tunable using "ctdb setvar"\.
+.PP
+If run with no parameter this will remove the reclock file completely\. If run
with a parameter the parameter specifies the new filename to use for the
recovery lock\.
+.PP
+This command only affects the runtime settings of a ctdb node and will be lost
when ctdb is restarted\. For persistent changes to the reclock file setting you
must edit /etc/sysconfig/ctdb\.
.SS "getdebug"
.PP
Get the current debug level for the node\. the debug level controls what
information is written to the log file\.
diff --git a/doc/ctdb.1.html b/doc/ctdb.1.html
index 7b20c87..a5413ab 100644
--- a/doc/ctdb.1.html
+++ b/doc/ctdb.1.html
@@ -295,7 +295,19 @@ CTDB version 1
This command is used to clear all statistics counters in a node.
</p><p>
Example: ctdb statisticsreset
- </p></div><div class="refsect2" lang="en"><a
name="id2528901"></a><h3>getdebug</h3><p>
+ </p></div><div class="refsect2" lang="en"><a
name="id2528901"></a><h3>getreclock</h3><p>
+ This command is used to show the filename of the reclock file that is
used.
+ </p><p>
+ Example output:
+ </p><pre class="screen">
+Reclock file:/gpfs/.ctdb/shared
+ </pre></div><div class="refsect2" lang="en"><a
name="id2528921"></a><h3>setreclock [filename]</h3><p>
+ This command is used to modify, or clear, the file that is used as the
reclock file at runtime. When this command is used, the reclock file checks are
disabled. To re-enable the checks the administrator needs to activate the
"VerifyRecoveryLock" tunable using "ctdb setvar".
+ </p><p>
+ If run with no parameter this will remove the reclock file completely.
If run with a parameter the parameter specifies the new filename to use for the
recovery lock.
+ </p><p>
+ This command only affects the runtime settings of a ctdb node and will
be lost when ctdb is restarted. For persistent changes to the reclock file
setting you must edit /etc/sysconfig/ctdb.
+ </p></div><div class="refsect2" lang="en"><a
name="id2528948"></a><h3>getdebug</h3><p>
Get the current debug level for the node. the debug level controls
what information is written to the log file.
</p><p>
The debug levels are mapped to the corresponding syslog levels.
@@ -305,40 +317,40 @@ CTDB version 1
The list of debug levels from highest to lowest are :
</p><p>
EMERG ALERT CRIT ERR WARNING NOTICE INFO DEBUG
- </p></div><div class="refsect2" lang="en"><a
name="id2528927"></a><h3>setdebug <debuglevel></h3><p>
+ </p></div><div class="refsect2" lang="en"><a
name="id2528974"></a><h3>setdebug <debuglevel></h3><p>
Set the debug level of a node. This controls what information will be
logged.
</p><p>
The debuglevel is one of EMERG ALERT CRIT ERR WARNING NOTICE INFO DEBUG
- </p></div><div class="refsect2" lang="en"><a
name="id2528943"></a><h3>getpid</h3><p>
+ </p></div><div class="refsect2" lang="en"><a
name="id2528989"></a><h3>getpid</h3><p>
This command will return the process id of the ctdb daemon.
- </p></div><div class="refsect2" lang="en"><a
name="id2528953"></a><h3>disable</h3><p>
+ </p></div><div class="refsect2" lang="en"><a
name="id2528999"></a><h3>disable</h3><p>
This command is used to administratively disable a node in the cluster.
A disabled node will still participate in the cluster and host
clustered TDB records but its public ip address has been taken over by
a different node and it no longer hosts any services.
- </p></div><div class="refsect2" lang="en"><a
name="id2528967"></a><h3>enable</h3><p>
+ </p></div><div class="refsect2" lang="en"><a
name="id2529013"></a><h3>enable</h3><p>
Re-enable a node that has been administratively disabled.
- </p></div><div class="refsect2" lang="en"><a
name="id2528977"></a><h3>ban <bantime|0></h3><p>
+ </p></div><div class="refsect2" lang="en"><a
name="id2529023"></a><h3>ban <bantime|0></h3><p>
Administratively ban a node for bantime seconds. A bantime of 0 means
that the node should be permanently banned.
</p><p>
A banned node does not participate in the cluster and does not host
any records for the clustered TDB. Its ip address has been taken over by an
other node and no services are hosted.
</p><p>
Nodes are automatically banned if they are the cause of too many
cluster recoveries.
- </p></div><div class="refsect2" lang="en"><a
name="id2529000"></a><h3>addip <public_ip/mask> <iface></h3><p>
+ </p></div><div class="refsect2" lang="en"><a
name="id2529047"></a><h3>addip <public_ip/mask> <iface></h3><p>
This command is used to add a new public ip to a node during runtime.
This allows public addresses to be added to a cluster without having
to restart the ctdb daemons.
</p><p>
Note that this only updates the runtime instance of ctdb. Any changes
will be lost next time ctdb is restarted and the public addresses file is
re-read.
If you want this change to be permanent you must also update the public
addresses file manually.
- </p></div><div class="refsect2" lang="en"><a
name="id2529021"></a><h3>delip <public_ip></h3><p>
+ </p></div><div class="refsect2" lang="en"><a
name="id2529067"></a><h3>delip <public_ip></h3><p>
This command is used to remove a public ip from a node during runtime.
If this public ip is currently hosted by the node it being removed
from, the ip will first be failed over to another node, if possible, before it
is removed.
</p><p>
Note that this only updates the runtime instance of ctdb. Any changes
will be lost next time ctdb is restarted and the public addresses file is
re-read.
If you want this change to be permanent you must also update the public
addresses file manually.
- </p></div><div class="refsect2" lang="en"><a
name="id2529042"></a><h3>moveip <public_ip> <node></h3><p>
+ </p></div><div class="refsect2" lang="en"><a
name="id2529088"></a><h3>moveip <public_ip> <node></h3><p>
This command can be used to manually fail a public ip address to a
specific node.
</p><p>
@@ -349,24 +361,24 @@ CTDB version 1
DeterministicIPs = 0
</p><p>
NoIPFailback = 1
- </p></div><div class="refsect2" lang="en"><a
name="id2529066"></a><h3>unban</h3><p>
+ </p></div><div class="refsect2" lang="en"><a
name="id2529113"></a><h3>unban</h3><p>
This command is used to unban a node that has either been
administratively banned using the ban command or has been automatically
banned by the recovery daemon.
- </p></div><div class="refsect2" lang="en"><a
name="id2529078"></a><h3>shutdown</h3><p>
+ </p></div><div class="refsect2" lang="en"><a
name="id2529125"></a><h3>shutdown</h3><p>
This command will shutdown a specific CTDB daemon.
- </p></div><div class="refsect2" lang="en"><a
name="id2529088"></a><h3>recover</h3><p>
+ </p></div><div class="refsect2" lang="en"><a
name="id2529135"></a><h3>recover</h3><p>
This command will trigger the recovery daemon to do a cluster
recovery.
- </p></div><div class="refsect2" lang="en"><a
name="id2529099"></a><h3>killtcp <srcip:port> <dstip:port></h3><p>
+ </p></div><div class="refsect2" lang="en"><a
name="id2529145"></a><h3>killtcp <srcip:port> <dstip:port></h3><p>
This command will kill the specified TCP connection by issuing a
TCP RST to the srcip:port endpoint. This is a command used by the
ctdb eventscripts.
- </p></div><div class="refsect2" lang="en"><a
name="id2529111"></a><h3>gratiousarp <ip> <interface></h3><p>
+ </p></div><div class="refsect2" lang="en"><a
name="id2529158"></a><h3>gratiousarp <ip> <interface></h3><p>
This command will send out a gratious arp for the specified interface
through the specified interface. This command is mainly used by the
ctdb eventscripts.
- </p></div><div class="refsect2" lang="en"><a
name="id2529124"></a><h3>reloadnodes</h3><p>
+ </p></div><div class="refsect2" lang="en"><a
name="id2529170"></a><h3>reloadnodes</h3><p>
This command is used when adding new nodes, or removing existing nodes
from an existing cluster.
</p><p>
Procedure to add a node:
@@ -400,7 +412,7 @@ CTDB version 1
</p><p>
5, Use 'ctdb status' on all nodes and verify that the deleted node no
longer shows up in the list..
</p><p>
- </p></div><div class="refsect2" lang="en"><a
name="id2529208"></a><h3>tickle <srcip:port> <dstip:port></h3><p>
+ </p></div><div class="refsect2" lang="en"><a
name="id2529254"></a><h3>tickle <srcip:port> <dstip:port></h3><p>
This command will will send a TCP tickle to the source host for the
specified TCP connection.
A TCP tickle is a TCP ACK packet with an invalid sequence and
@@ -412,10 +424,10 @@ CTDB version 1
TCP connection has been disrupted and that the client will need
to reestablish. This greatly speeds up the time it takes for a client
to detect and reestablish after an IP failover in the ctdb cluster.
- </p></div><div class="refsect2" lang="en"><a
name="id2529233"></a><h3>gettickles <ip></h3><p>
+ </p></div><div class="refsect2" lang="en"><a
name="id2529279"></a><h3>gettickles <ip></h3><p>
This command is used to show which TCP connections are registered with
CTDB to be "tickled" if there is a failover.
- </p></div><div class="refsect2" lang="en"><a
name="id2529244"></a><h3>repack [max_freelist]</h3><p>
+ </p></div><div class="refsect2" lang="en"><a
name="id2529290"></a><h3>repack [max_freelist]</h3><p>
Over time, when records are created and deleted in a TDB, the TDB list
of free space will become fragmented. This can lead to a slowdown in accessing
TDB records.
This command is used to defragment a TDB database and pruning the
freelist.
</p><p>
@@ -430,7 +442,7 @@ CTDB version 1
Example: ctdb repack 1000
</p><p>
By default, this operation is issued from the 00.ctdb event script
every 5 minutes.
- </p></div><div class="refsect2" lang="en"><a
name="id2529290"></a><h3>vacuum [max_records]</h3><p>
+ </p></div><div class="refsect2" lang="en"><a
name="id2529336"></a><h3>vacuum [max_records]</h3><p>
Over time CTDB databases will fill up with empty deleted records which
will lead to a progressive slow down of CTDB database access.
This command is used to prune all databases and delete all empty
records from the cluster.
</p><p>
@@ -446,12 +458,12 @@ CTDB version 1
Example: ctdb vacuum
</p><p>
By default, this operation is issued from the 00.ctdb event script
every 5 minutes.
- </p></div></div><div class="refsect1" lang="en"><a
name="id2529327"></a><h2>Debugging Commands</h2><p>
+ </p></div></div><div class="refsect1" lang="en"><a
name="id2529373"></a><h2>Debugging Commands</h2><p>
These commands are primarily used for CTDB development and testing and
should not be used for normal administration.
- </p><div class="refsect2" lang="en"><a
name="id2529337"></a><h3>process-exists <pid></h3><p>
+ </p><div class="refsect2" lang="en"><a
name="id2529384"></a><h3>process-exists <pid></h3><p>
This command checks if a specific process exists on the CTDB host.
This is mainly used by Samba to check if remote instances of samba are still
running or not.
- </p></div><div class="refsect2" lang="en"><a
name="id2529350"></a><h3>getdbmap</h3><p>
+ </p></div><div class="refsect2" lang="en"><a
name="id2529396"></a><h3>getdbmap</h3><p>
This command lists all clustered TDB databases that the CTDB daemon
has attached to. Some databases are flagged as PERSISTENT, this means that the
database stores data persistently and the data will remain across reboots. One
example of such a database is secrets.tdb where information about how the
cluster was joined to the domain is stored.
</p><p>
Most databases are not persistent and only store the state information
that the currently running samba daemons need. These databases are always wiped
when ctdb/samba starts and when a node is rebooted.
@@ -470,25 +482,25 @@ dbid:0x2672a57f name:idmap2.tdb
path:/var/ctdb/persistent/idmap2.tdb.0 PERSISTEN
dbid:0xb775fff6 name:secrets.tdb path:/var/ctdb/persistent/secrets.tdb.0
PERSISTENT
dbid:0xe98e08b6 name:group_mapping.tdb
path:/var/ctdb/persistent/group_mapping.tdb.0 PERSISTENT
dbid:0x7bbbd26c name:passdb.tdb path:/var/ctdb/persistent/passdb.tdb.0
PERSISTENT
- </pre></div><div class="refsect2" lang="en"><a
name="id2529396"></a><h3>catdb <dbname></h3><p>
+ </pre></div><div class="refsect2" lang="en"><a
name="id2529455"></a><h3>catdb <dbname></h3><p>
This command will dump a clustered TDB database to the screen. This is
a debugging command.
- </p></div><div class="refsect2" lang="en"><a
name="id2529407"></a><h3>getmonmode</h3><p>
+ </p></div><div class="refsect2" lang="en"><a
name="id2529466"></a><h3>getmonmode</h3><p>
This command returns the monutoring mode of a node. The monitoring
mode is either ACTIVE or DISABLED. Normally a node will continously monitor
that all other nodes that are expected are in fact connected and that they
respond to commands.
</p><p>
ACTIVE - This is the normal mode. The node is actively monitoring all
other nodes, both that the transport is connected and also that the node
responds to commands. If a node becomes unavailable, it will be marked as
DISCONNECTED and a recovery is initiated to restore the cluster.
</p><p>
DISABLED - This node is not monitoring that other nodes are available.
In this mode a node failure will not be detected and no recovery will be
performed. This mode is useful when for debugging purposes one wants to attach
GDB to a ctdb process but wants to prevent the rest of the cluster from marking
this node as DISCONNECTED and do a recovery.
- </p></div><div class="refsect2" lang="en"><a
name="id2529438"></a><h3>setmonmode <0|1></h3><p>
+ </p></div><div class="refsect2" lang="en"><a
name="id2529496"></a><h3>setmonmode <0|1></h3><p>
This command can be used to explicitely disable/enable monitoring mode
on a node. The main purpose is if one wants to attach GDB to a running ctdb
daemon but wants to prevent the other nodes from marking it as DISCONNECTED and
issuing a recovery. To do this, set monitoring mode to 0 on all nodes before
attaching with GDB. Remember to set monitoring mode back to 1 afterwards.
- </p></div><div class="refsect2" lang="en"><a
name="id2529453"></a><h3>attach <dbname></h3><p>
+ </p></div><div class="refsect2" lang="en"><a
name="id2529512"></a><h3>attach <dbname></h3><p>
This is a debugging command. This command will make the CTDB daemon
create a new CTDB database and attach to it.
- </p></div><div class="refsect2" lang="en"><a
name="id2529464"></a><h3>dumpmemory</h3><p>
+ </p></div><div class="refsect2" lang="en"><a
name="id2529523"></a><h3>dumpmemory</h3><p>
This is a debugging command. This command will make the ctdb
daemon to write a fill memory allocation map to standard output.
- </p></div><div class="refsect2" lang="en"><a
name="id2529476"></a><h3>rddumpmemory</h3><p>
+ </p></div><div class="refsect2" lang="en"><a
name="id2529535"></a><h3>rddumpmemory</h3><p>
This is a debugging command. This command will dump the talloc memory
allocation tree for the recovery daemon to standard output.
- </p></div><div class="refsect2" lang="en"><a
name="id2529487"></a><h3>freeze</h3><p>
+ </p></div><div class="refsect2" lang="en"><a
name="id2529546"></a><h3>freeze</h3><p>
This command will lock all the local TDB databases causing clients
that are accessing these TDBs such as samba3 to block until the
databases are thawed.
@@ -496,20 +508,20 @@ dbid:0x7bbbd26c name:passdb.tdb
path:/var/ctdb/persistent/passdb.tdb.0 PERSISTEN
This is primarily used by the recovery daemon to stop all samba
daemons from accessing any databases while the database is recovered
and rebuilt.
- </p></div><div class="refsect2" lang="en"><a
name="id2529506"></a><h3>thaw</h3><p>
+ </p></div><div class="refsect2" lang="en"><a
name="id2529564"></a><h3>thaw</h3><p>
Thaw a previously frozen node.
- </p></div><div class="refsect2" lang="en"><a
name="id2529515"></a><h3>eventscript <arguments></h3><p>
+ </p></div><div class="refsect2" lang="en"><a
name="id2476129"></a><h3>eventscript <arguments></h3><p>
This is a debugging command. This command can be used to manually
invoke and run the eventscritps with arbitrary arguments.
- </p></div><div class="refsect2" lang="en"><a
name="id2529527"></a><h3>backupdb <database> <file></h3><p>
+ </p></div><div class="refsect2" lang="en"><a
name="id2476141"></a><h3>backupdb <database> <file></h3><p>
This command can be used to copy the entire content of a database out
to a file. This file can later be read back into ctdb using the restoredb
command.
This is mainly useful for backing up persistent databases such as secrets.tdb
and similar.
- </p></div><div class="refsect2" lang="en"><a
name="id2529541"></a><h3>restoredb <file></h3><p>
+ </p></div><div class="refsect2" lang="en"><a
name="id2476155"></a><h3>restoredb <file></h3><p>
This command restores a persistent database that was previously backed
up using backupdb.
- </p></div></div><div class="refsect1" lang="en"><a
name="id2529553"></a><h2>SEE ALSO</h2><p>
+ </p></div></div><div class="refsect1" lang="en"><a
name="id2476167"></a><h2>SEE ALSO</h2><p>
ctdbd(1), onnode(1)
<a class="ulink" href="http://ctdb.samba.org/";
target="_top">http://ctdb.samba.org/</a>
- </p></div><div class="refsect1" lang="en"><a
name="id2529566"></a><h2>COPYRIGHT/LICENSE</h2><div
class="literallayout"><p><br>
+ </p></div><div class="refsect1" lang="en"><a
name="id2476180"></a><h2>COPYRIGHT/LICENSE</h2><div
class="literallayout"><p><br>
Copyright (C) Andrew Tridgell 2007<br>
Copyright (C) Ronnie sahlberg 2007<br>
<br>
diff --git a/doc/ctdb.1.xml b/doc/ctdb.1.xml
index 7b327fb..8d0c641 100644
--- a/doc/ctdb.1.xml
+++ b/doc/ctdb.1.xml
@@ -539,6 +539,36 @@ CTDB version 1
</para>
</refsect2>
+ <refsect2><title>getreclock</title>
+ <para>
+ This command is used to show the filename of the reclock file that is
used.
+ </para>
+
+ <para>
+ Example output:
+ </para>
+ <screen format="linespecific">
+Reclock file:/gpfs/.ctdb/shared
+ </screen>
+
+ </refsect2>
+
+ <refsect2><title>setreclock [filename]</title>
+ <para>
+ This command is used to modify, or clear, the file that is used as the
reclock file at runtime. When this command is used, the reclock file checks are
disabled. To re-enable the checks the administrator needs to activate the
"VerifyRecoveryLock" tunable using "ctdb setvar".
+ </para>
+
+ <para>
+ If run with no parameter this will remove the reclock file completely.
If run with a parameter the parameter specifies the new filename to use for the
recovery lock.
+ </para>
+
+ <para>
+ This command only affects the runtime settings of a ctdb node and will
be lost when ctdb is restarted. For persistent changes to the reclock file
setting you must edit /etc/sysconfig/ctdb.
+ </para>
+ </refsect2>
+
+
+
<refsect2><title>getdebug</title>
<para>
Get the current debug level for the node. the debug level controls
what information is written to the log file.
diff --git a/doc/ctdbd.1 b/doc/ctdbd.1
index 87d6581..73536a2 100644
--- a/doc/ctdbd.1
+++ b/doc/ctdbd.1
@@ -1,11 +1,11 @@
.\" Title: ctdbd
.\" Author:
.\" Generator: DocBook XSL Stylesheets v1.73.2 <http://docbook.sf.net/>
-.\" Date: 05/25/2009
+.\" Date: 06/25/2009
.\" Manual:
.\" Source:
.\"
-.TH "CTDBD" "1" "05/25/2009" "" ""
+.TH "CTDBD" "1" "06/25/2009" "" ""
.\" disable hyphenation
.nh
.\" disable justification (adjust text to left margin only)
@@ -131,7 +131,9 @@ If you omit this argument when using public addresses or
single public ip, ctdb
.PP
\-\-reclock=<filename>
.RS 4
-This is the name of the lock file stored of the shared cluster filesystem that
ctdbd uses to arbitrate which node has the role of recovery\-master\. This file
must be stored on shared storage\.
+This is the name of the lock file stored of the shared cluster filesystem that
ctdbd uses to prevent split brains from occuring\. This file must be stored on
shared storage\.
+.sp
+It is possible to run CTDB without a reclock file, but then there will be no
protection against split brain if the network becomes partitioned\. Using CTDB
without a reclock file is strongly discouraged\.
.RE
.PP
\-\-socket=<filename>
diff --git a/doc/ctdbd.1.html b/doc/ctdbd.1.html
index 4a953dd..1801090 100644
--- a/doc/ctdbd.1.html
+++ b/doc/ctdbd.1.html
@@ -82,8 +82,13 @@
</p><p>
If you omit this argument when using public addresses or single
public ip, ctdb will not be able to send out Gratious ARPs correctly or be able
to kill tcp connections correctly which will lead to application failures.
</p></dd><dt><span
class="term">--reclock=<filename></span></dt><dd><p>
- This is the name of the lock file stored of the shared cluster
filesystem that ctdbd uses to arbitrate which node has the role of
recovery-master.
+ This is the name of the lock file stored of the shared cluster
filesystem that ctdbd uses to prevent split brains from occuring.
This file must be stored on shared storage.
+ </p><p>
+ It is possible to run CTDB without a reclock file, but then there
+ will be no protection against split brain if the network becomes
+ partitioned. Using CTDB without a reclock file is strongly
+ discouraged.
</p></dd><dt><span
class="term">--socket=<filename></span></dt><dd><p>
This specifies the name of the domain socket that ctdbd will
create. This socket is used for local clients to attach to and communicate with
the ctdbd daemon.
</p><p>
@@ -115,10 +120,10 @@
implemented in the future.
</p></dd><dt><span class="term">--usage</span></dt><dd><p>
Print useage information to the screen.
- </p></dd></dl></div></div><div class="refsect1" lang="en"><a
name="id2528779"></a><h2>Private vs Public addresses</h2><p>
+ </p></dd></dl></div></div><div class="refsect1" lang="en"><a
name="id2528786"></a><h2>Private vs Public addresses</h2><p>
When used for ip takeover in a HA environment, each node in a ctdb
cluster has multiple ip addresses assigned to it. One private and one or
more public.
- </p><div class="refsect2" lang="en"><a name="id2528790"></a><h3>Private
address</h3><p>
+ </p><div class="refsect2" lang="en"><a name="id2528797"></a><h3>Private
address</h3><p>
This is the physical ip address of the node which is configured in
linux and attached to a physical interface. This address uniquely
identifies a physical node in the cluster and is the ip addresses
@@ -148,7 +153,7 @@
10.1.1.2
10.1.1.3
10.1.1.4
- </pre></div><div class="refsect2" lang="en"><a
name="id2528838"></a><h3>Public address</h3><p>
+ </pre></div><div class="refsect2" lang="en"><a
name="id2528845"></a><h3>Public address</h3><p>
A public address on the other hand is not attached to an interface.
This address is managed by ctdbd itself and is attached/detached to
a physical node at runtime.
@@ -209,7 +214,7 @@
unavailable. 10.1.1.1 can not be failed over to node 2 or node 3 since
these nodes do not have this ip address listed in their public
addresses file.
- </p></div></div><div class="refsect1" lang="en"><a
name="id2528920"></a><h2>Node status</h2><p>
+ </p></div></div><div class="refsect1" lang="en"><a
name="id2528927"></a><h2>Node status</h2><p>
The current status of each node in the cluster can be viewed by the
'ctdb status' command.
</p><p>
@@ -240,50 +245,50 @@
investigated and require an administrative action to rectify. This node
does not perticipate in the CTDB cluster but can still be communicated
with. I.e. ctdb commands can be sent to it.
- </p></div><div class="refsect1" lang="en"><a
name="id2528977"></a><h2>PUBLIC TUNABLES</h2><p>
+ </p></div><div class="refsect1" lang="en"><a
name="id2528984"></a><h2>PUBLIC TUNABLES</h2><p>
These are the public tuneables that can be used to control how ctdb
behaves.
- </p><div class="refsect2" lang="en"><a
name="id2528988"></a><h3>KeepaliveInterval</h3><p>Default: 1</p><p>
+ </p><div class="refsect2" lang="en"><a
name="id2528995"></a><h3>KeepaliveInterval</h3><p>Default: 1</p><p>
How often should the nodes send keepalives to eachother.
- </p></div><div class="refsect2" lang="en"><a
name="id2529001"></a><h3>KeepaliveLimit</h3><p>Default: 5</p><p>
+ </p></div><div class="refsect2" lang="en"><a
name="id2529008"></a><h3>KeepaliveLimit</h3><p>Default: 5</p><p>
After how many keepalive intervals without any traffic should a node
wait until marking the peer as DISCONNECTED.
- </p></div><div class="refsect2" lang="en"><a
name="id2529016"></a><h3>MonitorInterval</h3><p>Default: 15</p><p>
+ </p></div><div class="refsect2" lang="en"><a
name="id2529023"></a><h3>MonitorInterval</h3><p>Default: 15</p><p>
How often should ctdb run the event scripts to check for a nodes health.
- </p></div><div class="refsect2" lang="en"><a
name="id2529030"></a><h3>TickleUpdateInterval</h3><p>Default: 20</p><p>
+ </p></div><div class="refsect2" lang="en"><a
name="id2529037"></a><h3>TickleUpdateInterval</h3><p>Default: 20</p><p>
How often will ctdb record and store the "tickle" information used to
kickstart stalled tcp connections after a recovery.
- </p></div><div class="refsect2" lang="en"><a
name="id2529044"></a><h3>EventScriptTimeout</h3><p>Default: 20</p><p>
+ </p></div><div class="refsect2" lang="en"><a
name="id2529051"></a><h3>EventScriptTimeout</h3><p>Default: 20</p><p>
How long should ctdb let an event script run before aborting it and
marking the node unhealthy.
- </p></div><div class="refsect2" lang="en"><a
name="id2529059"></a><h3>RecoveryBanPeriod</h3><p>Default: 300</p><p>
+ </p></div><div class="refsect2" lang="en"><a
name="id2529066"></a><h3>RecoveryBanPeriod</h3><p>Default: 300</p><p>
If a node becomes banned causing repetitive recovery failures. The node
will
eventually become banned from the cluster.
This controls how long the culprit node will be banned from the cluster
before it is allowed to try to join the cluster again.
Dont set to small. A node gets banned for a reason and it is usually due
to real problems with the node.
- </p></div><div class="refsect2" lang="en"><a
name="id2529078"></a><h3>DatabaseHashSize</h3><p>Default: 100000</p><p>
+ </p></div><div class="refsect2" lang="en"><a
name="id2529085"></a><h3>DatabaseHashSize</h3><p>Default: 100000</p><p>
Size of the hash chains for the local store of the tdbs that ctdb manages.
- </p></div><div class="refsect2" lang="en"><a
name="id2529092"></a><h3>RerecoveryTimeout</h3><p>Default: 10</p><p>
+ </p></div><div class="refsect2" lang="en"><a
name="id2529099"></a><h3>RerecoveryTimeout</h3><p>Default: 10</p><p>
Once a recovery has completed, no additional recoveries are permitted
until this timeout has expired.
- </p></div><div class="refsect2" lang="en"><a
name="id2529106"></a><h3>EnableBans</h3><p>Default: 1</p><p>
+ </p></div><div class="refsect2" lang="en"><a
name="id2529113"></a><h3>EnableBans</h3><p>Default: 1</p><p>
When set to 0, this disables BANNING completely in the cluster and thus
nodes can not get banned, even it they break. Dont set to 0.
- </p></div><div class="refsect2" lang="en"><a
name="id2529121"></a><h3>DeterministicIPs</h3><p>Default: 1</p><p>
+ </p></div><div class="refsect2" lang="en"><a
name="id2529128"></a><h3>DeterministicIPs</h3><p>Default: 1</p><p>
When enabled, this tunable makes ctdb try to keep public IP addresses
locked to specific nodes as far as possible. This makes it easier for debugging
since you can know that as long as all nodes are healthy public IP X will
always be hosted by node Y.
</p><p>
The cost of using deterministic IP address assignment is that it disables
part of the logic where ctdb tries to reduce the number of public IP assignment
changes in the cluster. This tunable may increase the number of IP
failover/failbacks that are performed on the cluster by a small margin.
- </p></div><div class="refsect2" lang="en"><a
name="id2529146"></a><h3>DisableWhenUnhealthy</h3><p>Default: 0</p><p>
+ </p></div><div class="refsect2" lang="en"><a
name="id2529153"></a><h3>DisableWhenUnhealthy</h3><p>Default: 0</p><p>
When set, As soon as a node becomes unhealthy, that node will also
automatically become permanently DISABLED. Once a node is DISABLED, the only
way to make it participate in the cluster again and host services is by
manually enabling the node again using 'ctdb enable'.
</p><p>
This disables parts of the resilience and robustness of the cluster and
should ONLY be used when the system administrator is actively monitoring the
cluster, so that nodes can be enabled again.
- </p></div><div class="refsect2" lang="en"><a
name="id2529170"></a><h3>NoIPFailback</h3><p>Default: 0</p><p>
+ </p></div><div class="refsect2" lang="en"><a
name="id2529177"></a><h3>NoIPFailback</h3><p>Default: 0</p><p>
When set to 1, ctdb will not perform failback of IP addresses when a node
becomes healthy. Ctdb WILL perform failover of public IP addresses when a node
becomes UNHEALTHY, but when the node becomes HEALTHY again, ctdb will not fail
the addresses back.
</p><p>
Use with caution! Normally when a node becomes available to the cluster
ctdb will try to reassign public IP addresses onto the new node as a way to
distribute the workload evenly across the clusternode. Ctdb tries to make sure
that all running nodes have approximately the same number of public addresses
it hosts.
</p><p>
When you enable this tunable, CTDB will no longer attempt to rebalance the
cluster by failing IP addresses back to the new nodes. An unbalanced cluster
will therefore remain unbalanced until there is manual intervention from the
administrator. When this parameter is set, you can manually fail public IP
addresses over to the new node(s) using the 'ctdb moveip' command.
- </p></div></div><div class="refsect1" lang="en"><a
name="id2529206"></a><h2>LVS</h2><p>
+ </p></div></div><div class="refsect1" lang="en"><a
name="id2529213"></a><h2>LVS</h2><p>
LVS is a mode where CTDB presents one single IP address for the entire
cluster. This is an alternative to using public IP addresses and
round-robin
DNS to loadbalance clients across the cluster.
@@ -324,7 +329,7 @@ ctdb will try to reassign public IP addresses onto the new
node as a way to dist
the processing node back to the clients. For read-intensive i/o patterns
you can acheive very high throughput rates in this mode.
</p><p>
Note: you can use LVS and public addresses at the same time.
- </p><div class="refsect2" lang="en"><a
name="id2529279"></a><h3>Configuration</h3><p>
+ </p><div class="refsect2" lang="en"><a
name="id2529286"></a><h3>Configuration</h3><p>
To activate LVS on a CTDB node you must specify CTDB_PUBLIC_INTERFACE and
CTDB_LVS_PUBLIC_ADDRESS in /etc/sysconfig/ctdb.
</p><p>
@@ -347,7 +352,7 @@ You must also specify the "--lvs" command line argument to
ctdbd to activete LVS
all of the clients from the node BEFORE you enable LVS. Also make sure
that when you ping these hosts that the traffic is routed out through the
eth0 interface.
- </p></div><div class="refsect1" lang="en"><a
name="id2529326"></a><h2>REMOTE CLUSTER NODES</h2><p>
+ </p></div><div class="refsect1" lang="en"><a
name="id2529333"></a><h2>REMOTE CLUSTER NODES</h2><p>
It is possible to have a CTDB cluster that spans across a WAN link.
For example where you have a CTDB cluster in your datacentre but you also
want to have one additional CTDB node located at a remote branch site.
@@ -376,7 +381,7 @@ CTDB_CAPABILITY_RECMASTER=no
</p><p>
Verify with the command "ctdb getcapabilities" that that node no longer
has the recmaster or the lmaster capabilities.
- </p></div><div class="refsect1" lang="en"><a
name="id2529386"></a><h2>NAT-GW</h2><p>
+ </p></div><div class="refsect1" lang="en"><a
name="id2529393"></a><h2>NAT-GW</h2><p>
Sometimes it is desireable to run services on the CTDB node which will
need to originate outgoing traffic to external servers. This might
be contacting NIS servers, LDAP servers etc. etc.
@@ -399,7 +404,7 @@ CTDB_CAPABILITY_RECMASTER=no
if there are no public addresses assigned to the node.
This is the simplest way but it uses up a lot of ip addresses since you
have to assign both static and also public addresses to each node.
- </p><div class="refsect2" lang="en"><a
name="id2529426"></a><h3>NAT-GW</h3><p>
+ </p><div class="refsect2" lang="en"><a
name="id2529433"></a><h3>NAT-GW</h3><p>
A second way is to use the built in NAT-GW feature in CTDB.
With NAT-GW you assign one public NATGW address for each natgw group.
Each NATGW group is a set of nodes in the cluster that shares the same
@@ -414,7 +419,7 @@ CTDB_CAPABILITY_RECMASTER=no
In each NATGW group, one of the nodes is designated the NAT Gateway
through which all traffic that is originated by nodes in this group
will be routed through if a public addresses are not available.
- </p></div><div class="refsect2" lang="en"><a
name="id2529456"></a><h3>Configuration</h3><p>
+ </p></div><div class="refsect2" lang="en"><a
name="id2529463"></a><h3>Configuration</h3><p>
NAT-GW is configured in /etc/sysconfigctdb by setting the following
variables:
</p><pre class="screen">
@@ -453,31 +458,31 @@ CTDB_CAPABILITY_RECMASTER=no
# CTDB_NATGW_DEFAULT_GATEWAY=10.0.0.1
# CTDB_NATGW_PRIVATE_NETWORK=10.1.1.0/24
# CTDB_NATGW_NODES=/etc/ctdb/natgw_nodes
- </pre></div><div class="refsect2" lang="en"><a
name="id2529529"></a><h3>CTDB_NATGW_PUBLIC_IP</h3><p>
+ </pre></div><div class="refsect2" lang="en"><a
name="id2529508"></a><h3>CTDB_NATGW_PUBLIC_IP</h3><p>
This is an ip address in the public network that is used for all outgoing
traffic when the public addresses are not assigned.
This address will be assigned to one of the nodes in the cluster which
will masquerade all traffic for the other nodes.
</p><p>
Format of this parameter is IPADDRESS/NETMASK
- </p></div><div class="refsect2" lang="en"><a
name="id2529546"></a><h3>CTDB_NATGW_PUBLIC_IFACE</h3><p>
+ </p></div><div class="refsect2" lang="en"><a
name="id2529525"></a><h3>CTDB_NATGW_PUBLIC_IFACE</h3><p>
--
CTDB repository
