OGG : RMHOST compression

RMTHOST

Valid For

Extract

Description

Use the RMTHOST parameter to:

• Identify a remote system to which the local Extract process connects
• Specify the TCP/IP port number on that system where the Manager process is running
• Control various attributes of the TCP/IP connections

This parameter controls compression, data encryption, buffer attributes, TCP/IP streaming, connection timeout threshold, and the wait period for a connection request. It also can be used to set Collector parameters.

To identify multiple remote systems in a parameter file, use one RMTHOST statement for each one, followed by the associated trails and table maps, for example:

EXTRACT sales
USERIDALIAS tiger1
RMTHOST ny, MGRPORT 7888, ENCRYPT AES 192 KEYNAME mykey
RMTTRAIL /ggs/dirdat/aa
TABLE ora.orders;
RMTHOST la, MGRPORT 7888, ENCRYPT AES 192 KEYNAME mykey2
RMTTRAIL /ggs/dirdat/bb
TABLE ora.orders;

Do not use RMTHOST for an Extract created in PASSIVE mode. See "ADD EXTRACT" for more information about a passive Extract.

Oracle GoldenGate supports IPv4 and IPv6 protocols. See "USEIPV4" for more information about the selection of internet protocol.

The RMTHOST and RMTHOSTOPTIONS parameters can be specified together; the RMTHOST parameter is notrequired for RMTHOSTOPTIONS if the dynamic IP assignment is properly configured. When RMTHOSTOPTIONS is used, the MGRPORT option is ignored.

Default

None

Syntax

RMTHOST
{ host name | IP address}
[, COMPRESS]
[, COMPRESSTHRESHOLD]
[, ENCRYPT algorithm [KEYNAME key_name]]
{, MGRPORT port | PORT port}
[, CPU number]
[, PRI number]
[, HOMETERM device_name]
[, PROCESSNAME process_name]
[, PARAMS collector_parameters]
[, STREAMING | NOSTREAMING]
[, TCPBUFSIZE bytes]
[, TCPFLUSHBYTES bytes]
[, TIMEOUT seconds]

{host_name | IP_address}

The DNS host name or IP address of the target system. You can use either one to define the host. If using an IP address, use either an IPv6 or IPv4-mapped address, depending on the stack of the destination system.

COMPRESS

This option is valid for online or batch Extract processes and any Oracle GoldenGate initial-load method that uses trails. Compresses outgoing blocks of records to reduce bandwidth requirements. Oracle GoldenGate decompresses the data before writing it to the trail. COMPRESS typically results in compression ratios of at least 4:1 and sometimes better. However, compressing data can consume CPU resources.

COMPRESSTHRESHOLD

This option is valid for online or batch Extract processes and any Oracle GoldenGate initial-load method that uses trails. Sets the minimum block size for which compression is to occur. Valid values are from 0 and through 28000. The default is 1,000 bytes.

ENCRYPT algorithm [KEYNAME key_name]

This option is valid for online or batch Extract processes and all Oracle GoldenGate initial-load methods. Encrypts the data stream sent over TCP/IP to the target system. This option supports the following encryption options:

• Master key and wallet method: Generate a session key based on the active master key and algorithm specified. Not valid for DB2 on z/OS, DB2 for i, and SQL/MX.
• ENCKEYS method: Generate an AES encryption key, store it under a given name in an ENCKEYSfile, and configure Oracle GoldenGate to use that key to encrypt the data.

algorithm

Specifies the encryption algorithm to use:

• AES128 uses the AES-128 cipher, which has a key size of 128 bits. AES128 is the default if no algorithm is specified.
• AES192 uses the AES-192 cipher, which has a key size of 192 bits.
• AES256 uses the AES-256 cipher, which has a key size of 256 bits.
• BLOWFISH uses Blowfish encryption with a 64-bit block size and a variable-length key size from 32 bits to 128 bits. Use BLOWFISH for backward compatibility with earlier Oracle GoldenGate versions and for Oracle GoldenGate installations for DB2 on z/OS, DB2 for i, and SQL/MX on NonStop. On those platforms, BLOWFISH is the only supported encryption method. Use AES where supported, because it is more secure than BLOWFISH for those platforms.

KEYNAME key_name

Specifies that the ENCKEYS method of encryption will be used. Not valid for the master key and wallet method. For key_name, specify the logical name of the user-defined encryption key. Oracle GoldenGate uses the key name to look up the actual key in the ENCKEYS lookup file. To use the ENCKEYS method, you must:

• Generate the encryption key.
• Store it in an ENCKEYS lookup file.
• Copy ENCKEYS to every system where encryption or decryption (or both) are performed.

To use AES encryption for any database other than Oracle on a 32-bit platform, the path of the lib sub-directory of the Oracle GoldenGate installation directory must be specified as an environment variable before starting any processes. This is not required on 64-bit platforms. Set the path as follows:

• UNIX: Specify the path as an entry to the LD_LIBRARY_PATH or SHLIB_PATH variable. For example:

  setenv LD_LIBRARY_PATH ./lib:$LD_LIBRARY_PATH
  

• Windows: Add the path to the PATH variable.

You can use the SETENV parameter to set the library as a session variable for the process.

For more information about using encryption, see Administering Oracle GoldenGate for Windows and UNIX.

MGRPORT port | PORT port

Either MGRPORT or PORT is required. MGRPORT is the port on the remote system where Manager runs. PORTis the port number of a static Collector process. Either a Manager port (if using a dynamic Collector) or a static Collector port must be specified. See "Collector Parameters" for more information about a static Collector

CPU number

Valid for SQL/MX. Specifies the number of the CPU to be used for the process. Valid values are numbers 1 -15 and -1 is default, which is assigned 1 higher than the last Manager started.

PRI number

Valid for SQL/MX. Specifies the Extract process priority. Valid values are numbers are 1 - 199 and -1 is the default, and is the same as the manager process priority.

HOMETERM device_name

Valid for SQL/MX. Specifies the name of the device to be used and must be a terminal or process. It can be entered in either Guardian $ or OSS /G/xxxxx form. The default is $zhome or the current sessionHOMETERM when $zhome is not defined.

PROCESSNAME process_name

Valid for SQL/MX. Specifies the name of the process as alphanumeric string up to five characters and can be entered in either Guardian $ or OSS /G/xxxxx form. The default is a system generated process name.

PARAMS collector_parameters

Specifies Collector parameters on a NonStop target system

Note:

Do not specify a Collector port (-p argument) if Manager will be starting Collector dynamically.

For more information about Collector parameters on the NonStop platform, see Reference for Oracle GoldenGate for Mainframe for HP NonStop Guardian.

STREAMING | NOSTREAMING

This option is valid for online or batch Extract processes and any Oracle GoldenGate initial-load method that uses trails. Controls TCP/IP streaming.

STREAMING

Enables the asynchronous internet streaming protocol and is the default. In STREAMING mode, the receiver (Collector) does not send an acknowledgement to the sender (primary Extract or data pump) for any data packet unless the packet contains a flag requesting a response, typically when the sender must checkpoint or determine a write position. Because this method omits acknowledgements, the sender or receiver process terminates if there is a network disruption; therefore, when using STREAMING, use theAUTORESTART parameter in the Manager parameter file to restart Extract and Collector if they terminate.

NOSTREAMING

Enables the synchronous internet protocol. In NOSTREAMING mode, the sender sends a packet and then waits for the receiver to acknowledge it, before sending the next packet. This method is more reliable, because it enables the sender or receiver process to recover if there is a network disruption.

Extract falls back to the synchronous protocol automatically if the host system of the receiver process is not configured to use streaming.

Keep the STREAMING default unless you are requested to disable it, because streaming reduces transmission latency, especially in networks where latency is a problem already. Streaming is not supported for initial-load tasks where Extract communicates directly with Replicat.

TCPBUFSIZE bytes

This option is valid for online or batch Extract processes and any Oracle GoldenGate initial-load method that uses trails. Controls the size of the TCP socket buffer, in bytes, that Extract will try to maintain.

By increasing the size of the buffer, you can send larger packets to the target system.The actual size of the buffer depends on the TCP stack implementation and the network. The default is 30,000 bytes, but modern network configurations usually support higher values. Valid values are from 1000 to 200000000 (two hundred million) bytes. Work with your network administrator to determine an optimal value. See alsoAdministering Oracle GoldenGate for Windows and UNIX for more information about tuning the buffer size and other suggestions for improving the transfer of data across the network.

Testing has shown that using TCPBUFSIZE for initial loads produces three times faster throughput than loads performed without it. Do not use this parameter if the target system is NonStop.

TCPFLUSHBYTES bytes

This option is valid for online or batch Extract processes and any Oracle GoldenGate initial-load method that uses trails. Controls the size of the buffer, in bytes, that collects data that is ready to be sent across the network.

When either this value or the value of the FLUSHSECS parameter is reached, the data is flushed to the target. The default is 30,000 bytes. Valid values are from 1000 to 200000000 (two hundred million) bytes, but should be at least the value of TCPBUFSIZE.

Do not use this parameter for an initial load Extract. It is valid only for an online Extract group. Do not use this parameter if the target system is NonStop.

TIMEOUT seconds

This option is valid for online or batch Extract processes and any Oracle GoldenGate initial-load method that uses trails. Specifies how long Collector waits to get a connection from Extract, and how long Collector waits for a heartbeat signal from Extract before terminating a connection. Valid values are 1 second to 1800 seconds (30 minutes). The default value is 300 seconds (5 minutes). Setting the timeout to a very low value is not recommended in a production setting. You might need to increase the TIMEOUT value if you see a warning in the error log that there was a TCP/IP error 10054 (existing connection forcibly closed by remote host). This error typically occurs when the Collector terminates itself after the TIMEOUT value is exceeded. This parameter does not affect a static Collector.

Examples

Example 1   

RMTHOST 20.20.20.17, MGRPORT 7809, ENCRYPT AES192, KEYNAME newyork

Example 2   

RMTHOST 20.20.20.17, MGRPORT 7809, ENCRYPT AES192

Example 3   

RMTHOST newyork, MGRPORT 7809, COMPRESS, COMPRESSTHRESHOLD 750, NOSTREAMING

Example 4   

RMTHOST newyork, MGRPORT 7809, TCPBUFSIZE 100000, TCPFLUSHBYTES 300000

Example 5   

RMTHOST newyork, MGRPORT 18819, CPU 1, PRI 140, HOMETERM $ZTN0.#PTJ52A