From owner-svn-doc-all@FreeBSD.ORG Wed Apr 9 14:04:20 2014 Return-Path: Delivered-To: svn-doc-all@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [8.8.178.115]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id DE0F9B79; Wed, 9 Apr 2014 14:04:20 +0000 (UTC) Received: from svn.freebsd.org (svn.freebsd.org [IPv6:2001:1900:2254:2068::e6a:0]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id BEE921B9B; Wed, 9 Apr 2014 14:04:20 +0000 (UTC) Received: from svn.freebsd.org ([127.0.1.70]) by svn.freebsd.org (8.14.8/8.14.8) with ESMTP id s39E4KWd062448; Wed, 9 Apr 2014 14:04:20 GMT (envelope-from dru@svn.freebsd.org) Received: (from dru@localhost) by svn.freebsd.org (8.14.8/8.14.8/Submit) id s39E4Kgk062447; Wed, 9 Apr 2014 14:04:20 GMT (envelope-from dru@svn.freebsd.org) Message-Id: <201404091404.s39E4Kgk062447@svn.freebsd.org> From: Dru Lavigne Date: Wed, 9 Apr 2014 14:04:20 +0000 (UTC) To: doc-committers@freebsd.org, svn-doc-all@freebsd.org, svn-doc-head@freebsd.org Subject: svn commit: r44501 - head/en_US.ISO8859-1/books/handbook/disks X-SVN-Group: doc-head MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: svn-doc-all@freebsd.org X-Mailman-Version: 2.1.17 Precedence: list List-Id: "SVN commit messages for the entire doc trees \(except for " user" , " projects" , and " translations" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 09 Apr 2014 14:04:20 -0000 Author: dru Date: Wed Apr 9 14:04:20 2014 New Revision: 44501 URL: http://svnweb.freebsd.org/changeset/doc/44501 Log: White space fix only. Translators can ignore. Sponsored by: iXsystems Modified: head/en_US.ISO8859-1/books/handbook/disks/chapter.xml Modified: head/en_US.ISO8859-1/books/handbook/disks/chapter.xml ============================================================================== --- head/en_US.ISO8859-1/books/handbook/disks/chapter.xml Wed Apr 9 13:44:05 2014 (r44500) +++ head/en_US.ISO8859-1/books/handbook/disks/chapter.xml Wed Apr 9 14:04:20 2014 (r44501) @@ -3675,21 +3675,20 @@ Device 1K-blocks Used Av The goal of this example is to build a robust storage system which is resistant to the failure of any given node. - If the primary node - fails, the - secondary node is there to take over - seamlessly, check and mount the file system, and continue to - work without missing a single bit of data. - - To accomplish this task, the Common - Address Redundancy Protocol - (CARP) is used to provide for automatic failover at - the IP layer. CARP allows multiple hosts on the - same network segment to share an IP address. Set up - CARP on both nodes of the cluster - according to the documentation available in - . In this example, each node will - have its own management IP address and a + If the primary node fails, the secondary node is there to + take over seamlessly, check and mount the file system, and + continue to work without missing a single bit of + data. + + To accomplish this task, the Common Address Redundancy + Protocol (CARP) is used to provide for + automatic failover at the IP layer. + CARP allows multiple hosts on the same + network segment to share an IP address. + Set up CARP on both nodes of the cluster + according to the documentation available in . In this example, each node will have + its own management IP address and a shared IP address of 172.16.0.254. The primary HAST node of the cluster must be the @@ -3699,10 +3698,11 @@ Device 1K-blocks Used Av section is now ready to be exported to the other hosts on the network. This can be accomplished by exporting it through NFS or - Samba, using the shared IP - address 172.16.0.254. The only - problem which remains unresolved is an automatic failover - should the primary node fail. + Samba, using the shared + IP address + 172.16.0.254. The only problem + which remains unresolved is an automatic failover should the + primary node fail. In the event of CARP interfaces going up or down, the &os; operating system generates a @@ -3714,9 +3714,8 @@ Device 1K-blocks Used Av which will automatically handle the HAST failover. To catch state changes on the - CARP interfaces, add this - configuration to - /etc/devd.conf on each node: + CARP interfaces, add this configuration + to /etc/devd.conf on each node: notify 30 { match "system" "IFNET"; @@ -3743,16 +3742,16 @@ notify 30 { &prompt.root; service devd restart - When the specified interface state - changes by going up or down , the system generates a - notification, allowing the &man.devd.8; subsystem to run the - specified automatic failover script, + When the specified interface state changes by going up + or down , the system generates a notification, allowing the + &man.devd.8; subsystem to run the specified automatic + failover script, /usr/local/sbin/carp-hast-switch. - For further - clarification about this configuration, - refer to &man.devd.conf.5;. + For further clarification about this configuration, refer to + &man.devd.conf.5;. - Here is an example of an automated failover script: + Here is an example of an automated failover + script: #!/bin/sh @@ -3857,8 +3856,7 @@ esac - When a node becomes - secondary: + When a node becomes secondary: @@ -3872,16 +3870,18 @@ esac - This is just an example script which - serves as a proof of concept. It does not handle all the - possible scenarios and can be extended or altered in any - way, for example, to start or stop required services. + This is just an example script which serves as a proof + of concept. It does not handle all the possible scenarios + and can be extended or altered in any way, for example, to + start or stop required services. - For this example, a standard UFS file system was used. - To reduce the time needed for recovery, a journal-enabled - UFS or ZFS file system can be used instead. + For this example, a standard UFS + file system was used. To reduce the time needed for + recovery, a journal-enabled UFS or + ZFS file system can be used + instead. More detailed information with additional examples can @@ -3902,21 +3902,21 @@ esac When troubleshooting HAST, the debugging level of &man.hastd.8; should be increased by - starting hastd with -d. This - argument may be specified multiple times to further increase - the debugging level. Consider also using - -F, which starts hastd in the - foreground. + starting hastd with -d. + This argument may be specified multiple times to further + increase the debugging level. Consider also using + -F, which starts hastd + in the foreground. Recovering from the Split-brain Condition - Split-brain occurs when the nodes of the - cluster are unable to communicate with each other, and both - are configured as primary. This is a dangerous condition - because it allows both nodes to make incompatible changes to - the data. This problem must be corrected manually by the - system administrator. + Split-brain occurs when the nodes + of the cluster are unable to communicate with each other, + and both are configured as primary. This is a dangerous + condition because it allows both nodes to make incompatible + changes to the data. This problem must be corrected + manually by the system administrator. The administrator must decide which node has more important changes or merge them manually. Then, let