Dynamically configuring data sets for channel-attached devices

You can dynamically configure channel-attached devices in your network.

Procedure

To prepare your system to support dynamic configuration of channel-attached devices, perform the following steps during your installation. See z/OS Communications Server: SNA Network Implementation Guide for a full description of this support.

Define USER1.AUTO.VTAMLST as a partitioned data set. You can customize the name of the data set by altering its name in the ISTDEFIN command list. A sample of ISTDEFIN is found in SYS1.SAMPLIB.
Concatenate the USER1.AUTO.VTAMLST data set to the SYS1.VTAMLST data set as defined on the VTAMLST DD statement in the z/OS® Communications Server start procedure. You also need to code the AUTO.VTAMLST data set as shared (DISP=SHR):
```
⋮
//VTAMLST  DD DSN=SYS1.VTAMLST,DISP=SHR
           DD DSN=USER1.AUTO.VTAMLST,DISP=SHR
⋮
```
USER1.AUTO.VTAMLST is used by ISTDEFIN for storing automatically generated major nodes. Each member of USER1.AUTO.VTAMLST representing a data host will then contain the definition for just one device. A local SNA major node will also include any of its associated LUs.
Set the data set control block (DCB) information for this data set with the same values as for the other VTAMLST data sets.

Define a catalog entry checkpoint data set (AUTOCKPT) for dynamic configuration support:

DEFINE
  CLUSTER(NAME('VSAM.AUTOCKPT') -
          VOL(PUBLIC) -
          KEYS(4 0) -
          DATA(NAME('VSAM.AUTOCKPT.DATA')-
          RECORDS(200 20) -
          RECORDSIZE(24 136)) -
  INDEX(NAME(VSAM.AUTOCKPT.INDEX) -
          TRACKS(1))

Add this data set using the AUTOCKPT DD statement in the z/OS Communications Server start procedure:
```
⋮
//AUTOCKPT DD DSN=VSAM.AUTOCKPT,AMP=AMORG,DISP=OLD
⋮
```