Sharing printers with an ESCON or FICON channel

Figure 8 shows an example of using an ESCON® or a FICON® channel to share a printer between LPARs.

Figure 8. Example of a shared ESCON or FICON channel-attached printer

If the processor complex has ESCON Multiple Image Facility (EMIF) and is in LPAR mode, a path from each LPAR can be configured online concurrently to the printer. For those printers that support the multi-host feature, access to the printer is controlled by:

1. Doing these on the host that has access to the printer:
   1. Draining PSF
   2. Varying the printer offline
2. Doing these on the other host:
   1. Varying the printer online
   2. Starting PSF

For more information about LPAR mode and EMIF, see the Processor Resource/Systems Manager Planning Guide for your processor.

Figure 9 shows the parameters required for defining a shared ESCON or FICON channel-attached printer with multi-host support.

CHPID PATH=20,TYPE=CNC or FC,SHARED,PART=(LPAR1,LPAR2)
CNTLUNIT CUNUMBR=400,PATH=20,UNITADD=10,UNIT=AFP1
IODEVICE CUNUMBR=400,UNIT=AFP1,ADDRESS=2010

For those printers that do not support the multi-host feature, only one path from each LPAR can be configured online to the printer. Access to the printer is controlled by:

1. Doing these on the host that has access to the printer:
   1. Draining PSF
   2. Varying the printer offline
   3. Configuring the path offline from the LPAR
2. Doing these on the other host:
   1. Configuring the path online to the LPAR
   2. Varying the printer online
   3. Starting PSF

All channel paths must be ESCON or FICON; they cannot be intermixed.

Figure 10 shows the parameters required for defining a shared ESCON or FICON channel-attached printer without multi-host support.

CHPID PATH=20,TYPE=CNC or FC,PART=[(0),(LPAR1,LPAR2),REC]
CNTLUNIT CUNUMBR=400,PATH=20,UNITADD=10,UNIT=AFP1
IODEVICE CUNUMBR=400,UNIT=AFP1,ADDRESS=2010