Copy Image Copy function

Purpose of the CIC function

The CIC function reads an input image copy data set and creates one or more output copies of that data set.

The timestamp on the output data set is the same as the timestamp on the original data set. The following figure shows the processing flow of the CIC function.

You can use the CIC function for the following purposes:

• To create additional output copies of the input data set, such as to send offsite or to use for testing
• To replace an existing copy with an identical copy, such as a copy that might be required for an image copy data set that has been flagged as in error
• To move Image Copy dataset (that is recorded in the RECON dataset) from one media type to another
• To transform the input copy into a different format, such as in the following examples:
  • read an Instant Snapshot copy and write a traditional image copy (which can be compressed or encrypted)
  • read an encrypted image copy and write an image copy that is not encrypted, or read an image copy that is not encrypted and write an encrypted image copy
  • read a compressed image copy and write an uncompressed image copy, or read a compressed image copy and write a compressed image copy that uses different compression characteristics
  • read an image copy and write it to a stacked tape that contains other image copies, or read an image copy from a stacked tape and write it to an unstacked tape or to DASD\

Creating traditional copies from Instant Snapshot copies

If the input to the CIC function is an Instant Snapshot copy, the output data set is a traditional image copy.

Generally, the Image Copy utility cannot process the same data set group or area more than once in the same job step. Usually you cannot use the CIC function in the same job step with other utility functions that process the same data set group or area. However, if the function is producing an Instant Snapshot copy (the DSSNAP keyword is specified on the IC, AIC, OIC, or AOIC control statement), you can use the CIC function (by including a CIC or ACIC statement) in the same job step for the same data set group or area to produce one or more traditional image copies with the Instant Snapshot copy.

The CIC function uses DBRC to determine the type of the input data set. If DBRC is not active for the function and the input data set is an Instant Snapshot copy, you must specify the DUMPTYPE(I) keyword on the CIC or ACIC statement to identify that the input is an Instant Snapshot copy.

Reading and writing encrypted image copy data sets

The CIC function can read and write encrypted image copy data sets.

The function automatically detects that an input copy is encrypted. The function can encrypt the output image copy data set if encryption is specified in the dynamic allocation model that is used to allocate the output data set. The function also considers DBRC notification in determining whether to encrypt the output copy. For more information, see DBRC considerations for the CIC function.

If a single job step creates an Instant Snapshot copy and a traditional image copy through the CIC function, the secondary copy (copy 2) can be encrypted.

If you want to create a physical copy of an encrypted image copy (so that the output copy is encrypted with the same encryption key as the input copy), the CIC function can bypass the decryption and encryption processes to save time and resources. To create a physical copy, ensure that the BMCICPKF dynamic allocation member is not present in the IMSDALIB, MDALIB, DFSRESLB, or STEPLIB and specify the ASIS(Y) keyword on the GLBL, GROUP, CIC, or ACIC control statement.

Reading and writing compressed image copy data sets

If the input is a traditional image copy data set, the output image copy data set can be a physical copy or a logical copy of the original.

In a physical copy, the new data set retains the characteristics of the original image copy data set. In a logical copy, the new data set is created by expanding the input (if it was previously compressed) and recompressing the data with the same or a different compression algorithm.

When an input image copy data set is compressed, the physical copy process is the most efficient way to create additional image copies. If you must change compression characteristics or perform simultaneous pointer checking, you must use the logical copy process.

To create a physical copy, specify the ASIS(Y) keyword on the GLBL, GROUP, CIC, or ACIC control statement. To create a logical copy, use the default, ASIS(N).

Using secondary image copies as input to the CIC function

You can use the SIC keyword to dynamically allocate a secondary image copy (copies 2 through 10) for input.

This copy can be an encrypted image copy. Copies 3 through 10 are allocated through the Recovery Extensions feature.

Moving an image copy dataset recorded in the RECON dataset from one media type to another

This function enables automatic movement of the DASD image copies to stacked or unstacked tapes, updates the recon image copy record to reflect the new image copy data set and deletes the original DASD copy.

Keyword MOVEIC is added to the ACIC/CIC command which can have a value of either Image Copy 1 (IC1) or Image Copy 2 (IC2). MOVEIC(IC1) or MOVEIC(IC2) indicates the data set recorded in the recon is to be replaced with the new output CIC data set.

A timestamp value can be provided to select the image copy record in the recon to be processed. If no timestamp is supplied, the last IC recorded in the recon is considered by default.

DBRC considerations for the CIC function

The use of DBRC is optional with the CIC function.

If you use DBRC, the following conditions apply:

• The CIC function creates a new image copy data set with the same timestamp as the original data set. DBRC records information about a primary image copy and can also record information about the first secondary image copy (copy 2). If only one image copy data set is recorded or if either recorded copy has been marked in error by DBRC, the CIC function automatically causes DBRC to update its records to include the new image copy data sets.

  The CIC function can use the Recovery Extensions feature to register additional copies (copies 3 through 10) in the Recovery Manager repository.

• The Image Copy utility does not require DBRC database READ authorization to perform the CIC function. The CIC function can be executed while the database is allocated to an IMS online region.
• If you use a secondary copy as input to the CIC function for the purpose of replacing the primary copy (copy 1) because the primary copy is in error, the job step terminates abnormally if encryption is specified for the output (replacement) copy. Otherwise, the primary copy is replaced with the output copy.
• If you use the first secondary image copy (copy 2) as input to the CIC function and if the primary image copy (copy 1) is not flagged in error, the function bypasses DBRC notification of an output copy. This action occurs whether or not the output copy is encrypted.
• If you use the primary image copy as input to the CIC function, the function notifies DBRC that the output copy is the first secondary copy (copy 2). If copy 2 already exists, the function bypasses DBRC notification of the copy. These actions occur whether or not the output copy is encrypted.
• Occasionally you may want to run multiple CIC functions and use the same original input, such as when you are determining which compression algorithm is best for the database. In this case you should deactivate DBRC. Reactivate DBRC for the CIC function only when you are creating a data set that subsequently will be used for recovery.
• If DBRC is active, the CIC function can dynamically allocate the input image copy data set, based on the information that is recorded in the RECON data set.
• If DBRC is active, you can use the VERIFY keyword to ensure that the latest image copy data set that is recorded in DBRC is used as input to the CIC function.
• If you do not want to use the last image copy data set as input to the CIC function, use the TIMESTMP keyword to specify the timestamp of the image copy that you want to use.
• If DBRC is active with VERIFY(N) specified, the CIC function registers the new image copy data set, based on the timestamp and type flags that are found in the header record of the input image copy.