{"id":2042,"date":"2017-06-28T09:18:47","date_gmt":"2017-06-28T08:18:47","guid":{"rendered":"https:\/\/www.threesl.com\/blog\/?p=2042"},"modified":"2022-11-10T14:38:19","modified_gmt":"2022-11-10T14:38:19","slug":"multiple-cradle-database-servers-and-how-to-connect-to-them","status":"publish","type":"post","link":"https:\/\/www.threesl.com\/blog\/multiple-cradle-database-servers-and-how-to-connect-to-them\/","title":{"rendered":"Multiple Cradle Database Servers and How to Connect to Them"},"content":{"rendered":"

Multiple Cradle Database Server (CDS) Environments<\/h2>\n

Cradle supports multiple Cradle database servers,\u00a0 in a single environment, based on the CDS Host Access List<\/em>. The following file contains a list of the TCP\/IP<\/em> hostnames of the hosts that the CDS<\/em> will respond to:<\/p>\n

Windows –<\/strong> %CRADLEHOME%\\admin\\cds_hosts<\/p>\n

Linux –<\/strong> $CRADLEHOME\/admin\/cds_hosts<\/p>\n

The file is empty by default, which mean a CDS<\/em> will respond to all hosts.<\/p>\n

Two or more Cradle systems may be installed and operate in the same network by ensuring that each CDS<\/em> has a non-empty Host Access List<\/strong> that defines the lists of hosts that are to be serviced by that CDS<\/em>.\u00a0 Multiple Cradle systems are consequently achieved by ensuring that the hosts used to run the CDS<\/em>s appear in the Host Access List<\/strong> of only one CDS<\/em>.<\/p>\n

\"multiple
Multiple CDS on the same network<\/figcaption><\/figure>\n

Clients Connecting to Multiple CDS<\/h2>\n

Each Cradle<\/em> client such as WorkBench<\/em> may be executed on a host which is in the Host Access List<\/strong> of more than one CDS<\/em>. In this case, WorkBench<\/em> should be told which CDS<\/em> it is to connect to, for example by using the command-line option: -cds hostname<\/em><\/samp><\/p>\n

Methods of connecting Cradle tools to a CDS<\/h3>\n

There are several methods of specifying which CDS, <\/em>when you have multiple Cradle<\/em> database servers, <\/em>a client is to use, or alternatively a client can attempt automatic CDS<\/em> discovery.<\/p>\n

-cds command line option<\/h4>\n

Cradle<\/em> tools for example the WorkBench<\/em> client, supports a -cds<\/em> command line option that takes an argument which is interpreted to be either the hostname or IP address of the machine where the CDS is executing.<\/p>\n

-cds hostname<\/em><\/samp><\/p>\n

If invoked with this command line option, the WorkBench<\/em> client does not attempt CDS discovery via broadcast, but instead attempts to link directly to the CDS<\/em> on the specified machine.<\/p>\n

CRADLE_CDS_HOST environment variable<\/h4>\n

If a -cds command<\/em> line option has not been specified, the WorkBench<\/em> client tests for the presence of a CRADLE_CDS_HOST<\/samp> environment variable, and if defined, uses its value as the hostname<\/em> or IP address<\/em> of the host executing the CDS<\/em>.<\/p>\n

In this case, WorkBench<\/em> does not attempt CDS<\/em> discovery via broadcast, but instead attempts to link directly to the CDS<\/em> on the specified machine.<\/p>\n

Automatic CDS discovery by broadcast<\/h4>\n

If a CDS<\/em> host has not been specified through other means (such as via the \u2013cds<\/samp> command-line option, or CRADLE_CDS_HOST<\/samp> environment variable), a Cradle client such as WorkBench<\/em> will attempt to locate a CDS<\/em> automatically by broadcasting. If the client can connect to two or more CDS<\/em>s and is using this method, the client will connect to which ever CDS<\/em> responds quickest.<\/p>\n

For a more in-depth look at environments with multiple Cradle database servers,\u00a0<\/em> please refer to our online help<\/a>.<\/p>\n