Compression mode, Circuit keep alive time out values, Srdf considerations – Brocade Network Advisor SAN User Manual v12.3.0 User Manual

Page 1008

Advertising
background image

956

Brocade Network Advisor SAN User Manual

53-1003154-01

Connecting cascaded FICON fabrics over FCIP

22

Compression mode

More aggressive compression modes can be used for asynchronous mirroring. For synchronous
mirroring, only hardware or standard compression should be used. This is because more
aggressive algorithms work by receiving additional frames to find compressible patterns on larger
blocks of data. The time it takes to read in these additional frames add latency, which may not be
tolerated by synchronous mirroring. Set compression modes on the Add FCIP Tunnel dialog box.

Circuit Keep Alive Time Out values

The circuit Keep Alive Time Out value, located on the Transmission tab of FCIP Circuit Advanced
Settings dialog box, should be less than the protocol timeout for the application being extended.
This allows circuit failover to be non-disruptive. By default, the circuit keep alive is 10 seconds
(10000 ms) and 1 second (1000 ms) for FICON. Set this to 6 seconds (6000 ms) for IBM
peer-to-peer remote copy (PPRC). All other applications should use the default.

SRDF considerations

Use SRDF/S SiRT (Single Roundtrip) or SRDF/A with FCIP-FW but not both. Using SRDF/A and
SRDF/S on the same remote adapter (RA) ports on the array is not recommended. Use different
VE_Ports for the tunnels, as if the tunnel destinations are different. If there is only one destination
(SRDF/A and SRDF/S are going to the same place), isolate traffic from the SRDF/A and SRDF/S RA
ports using TI zones and configure the tunnels accordingly. Note that there may be differences in
bandwidth, Fast Write, and compression mode tunnel parameters.

EMC

MirrorView

CLARiiON

Sync

Yes

EMC

SANcopy

CLARiiON

Async

Yes

HDS

Universal Replicator
(HUR)

All

Async

No

HDS

TrueCopy

All

Async

No

HP

Continuous Access

EVA

Hybrid

No

*

OSTP

Tape

Tape

Yes (required for OSTP)

TABLE 77

Using Fast Write for extended applications

Manufacturer

RDR Application

Platform

Type

Use Fast Write

Advertising