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Define mirrors that include this instance.


[Mirrors]    Name=a,b,c,d,e,f,g,h,i,j|k,l,m,n,o,p


The [Mirrors] section contains an entry for each mirror connected to the current InterSystems IRIS® data platform instance. The entries are made up of a Name and 14 comma-separated values (an), as follows:

  • Name – Required. Unique name by which you can identify this mirror. An uppercase alphanumeric string with a maximum length of 15 characters.

  • a (GUID) – Required. An internal GUID, unique to this mirror.

  • b (2) – For internal use.

  • c (1) – For internal use.

  • d (Defined Primary) – Used to disable mirror failover, generally for maintenance purposes. Manipulated via the nofailover option when shutting down InterSystems IRIS or the ^MIRROR routine. This contains the mirror name of the member which must be the primary. It is cleared automatically when that node starts up and becomes the primary.

  • e (QOSTimeout) – Quality of Service Timeout: the maximum time, in milliseconds, that a failover member waits for a response from the other failover member before taking action; also applies to the arbiter’s wait for a failover member’s response. The default is 8000ms; typically, deployments on physical (non-virtualized) hosts with a dedicated local network can reduce this setting if a faster response to outages is required. See Configuring the Quality of Service (QoS) Timeout Setting for more information on the QoS Timeout setting.

  • f (0) – For internal use.

  • g (UseSSL) – To provide security within a mirror, you can configure its nodes to use SSL/TLS. This provides for both authentication of one node to another, and for encrypted communication between nodes. To use SSL/TLS with a mirror, each member (failover or async) uses a pair of SSL/TLS configurations, %Mirror_Client and %Mirror_Server. These configurations must already exist on each member when SSL/TLS is enabled for the mirror. Instructions for setting up SSL are in Create and Edit TLS Configurations for a Mirror. Values are 0 (no, default) or 1 (yes).

  • h (VirtualAddress) – Specifies a virtual IP address. You can configure a mirror virtual IP address (VIP) so that all external clients (language bindings, ODBC/JDBC/SQL clients, and so on) connect to the mirror through a single address. This virtual IP address is automatically bound to an interface on the current primary member. To use a VIP, both failover members must be on the same subnet. For more information, see Configuring a Mirror Virtual IP (VIP).

  • i (0) – For internal use.

  • j (ArbiterNode) – The network address of the arbiter configured for this mirror. The arbiter is an independent instance hosting an ISCAgent with which the failover members of a mirror maintain continuous contact, providing them with the context needed to safely make failover decisions when they cannot communicate directly.

  • k (ArbiterPort) – The port used by the configured arbiter’s ISCAgent process (2188 by default). Appears in the same space as j, separated by a vertical bar.

  • l (CompressionForFailoverMembers) – Determines whether journal data is compressed before being transmitted from the primary to the backup. Possible values are 0 (System Selected, which optimizes for response time between failover members), 1 (Uncompressed), and 2 (Compressed).

  • m (CompressionForAsyncMembers) – Determines whether journal data is compressed before being transmitted from the primary to async members. Possible values are 0 (System Selected, which optimizes for network utilization), 1 (Uncompressed), and 2 (Compressed).

  • n (AllowParallelDejournaling) – Determines which type of mirror members can run parallel dejournaling updaters. Possible values are 0 (failover and disaster recover members), 1 (failover members only), and 2 (all members).

  • o (CompressionTypeForFailoverMembers) – Determines the compression type for CompressionForFailoverMembers. Possible values are 0 (ZLIB), 1 (ZSTD), and 2 (LZ4).

  • p (CompressionTypeForAsyncMembers) – Determines the compression type for CompressionForAsyncMembers. Possible values are 0 (ZLIB), 1 (ZSTD), and 2 (LZ4).

For more information on Mirroring, see Mirroring.

Management Portal

On the Create a Mirror page of the Management Portal (System Administration > Configuration > Mirror Settings > Create a Mirror), enter the requested information. You can edit an existing mirror on the Edit Mirror page, but only from the primary failover member.

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