Features

MFNetDisk Emulates 3390 disks and tapes on PC without using expensive hardware or without distance imitation.

MFNetDisk replicates any real 3390 disk (IBM, EMC or HDS) with any disk capacity, without performance degradation, and without any expensive hardware (only PC and hard disk needed)

MFNetDisk Supports eight mirrors for each MFNetDisk virtual disk or real disk.

MFNetDisk PC DEVICE is cotainer which define one MF disk device and its mirrors.

Each PC Device mirror in PC can contain 8 mirrors which can be real MVS DISK mirrors or local mirror PC files which contain the 3390 data.

Each PC file mirror (standard Linux or Windows files) can be emulated with MFNetDisk in MF the same as real 3390 disk work in MF)

Each MFNetDisk mirror can be a Net File (MVS real 3390 disk at any remote location) or remote PC device in remote PC) or PC File (local PC file).

MFNetDisk in MF contained parameters file which defined the connection between the MF 3390 device number to the PC PC Devcie number.

An MF host can be connected to an unlimited number of PC hosts using TCP/IP.

Example: MF device number 300 can be emulated by PC1 with IP1 while MF device number 301 can be emulated by PC2 with IP2.

The link between the MF device number and MFNetDisk PC device is done by using the MFNetDisk parameters which are defined in the MVS MF.

MFNETDISK PC Device is defined in PC Host.

MVS defines the link between PC Device and MVS device.

An active PC Device can have one or more Mirrors.

A Mirror definition in PC Device contains all the information which, is needed to control the mirror and the location of the mirror. If more than one mirror is defined to the PC Device, MFNETDISK will make sure that all the mirrors have equal data (using ReSync).

A mirror can be PC File or Net File.

PC Device contains all the mirrors disk definitions.

PC Device type can be Replicator(mirror any real 3390 disks) or Emulator (emulate 3390 disks).

MFNetDisk uses Emulator PC Device to emulate 3390 disks with data in the PC the same way as IBM, EMC or HDS emulates 3390 disks.

MFNetDisk uses replicator PC device to mirror any real 3390 disks (IBM, EMC or HDS) to Net File or PC File mirrors. The source real 3390 is never updated by MFNetDisk. Only the target mirrors are ReSyncs by MFNetDisk to contain the same data as the source real 3390 disk mirror.

A Mirror can be either a PC File or a Net File.

Net File -

Net File is a 3390 Mirror with data in the net.

Net can be remote or local MVS real device or remote PC host PC device.

PC File -

PCFILE is Mirror with data in a regular PC File which can be accessed by MFNetDisk server locally.

MFNetDisk Accesses the mirror data by using standard Windows or Linux Filesystem.

Mirror can be in one of the following status:

Sync

The mirror is valid for all IO.

ReqSync

The mirror is validating its tracks to become Sync.

ReadOnly

The mirror is valid only for read IO.

Suspend

The Mirror is temporarily closed and cannot be accessed for IO.

Offline

The mirror is not defined.

AsyncSource

The Mirror is the Source mirror for replicator PC Device.

Ability to share Emulator PC Device (also MVS real Device) by unlimited MVS MF hosts (real MF or emulated MF) without distance limitation nor hardware connection.

MFNetDisk uses TCP/IP protocol and RESERVE / RELEASE CCWs to share the MFNetDisk emulated 3390 and keeping the data integrity of the data.

Sharing the MFNetDisk 3390 disks is done by using BusyIO feature, which enables the product to use the Device busy condition (Reserve CCW and Define Extent CCW conflict) the same way as MVS does.

Busy device condition in MFNetDisk put the IO request in a wait state without blocking the MFNetDisk tasks in MVS.

MVS MFNetDisk restarts The IO request only after receiving the Device end status from the PC MFNetDisk when the busy device condition is cleared.

Emulator (Sync) mode

MFNetdisk emulates 3390 disks and 3490 tapes the same way as IBM emulates Shark and tapes and EMC emulates Symmetrix and tapes.

MVS sees the MFNetDisk virtual disks and tapes the same as a regular real 3390 or 3490.

MFNetDisk uses PC storage (example: Hard Disks) to store the data of the emulated 3390 disks and 3490 tapes.

Replicator (ASync) mode

MFNetDisk can mirror any real 3390 without degradation in the performance and without any I/O delay. In this method, MFNetDisk analyzes the IO and without delay or change to the IO, MFNetDisk lets the real disk to run the IO.

For write IO only, MVS MFNetDisk analyzes the CCW chain and create a compressed list of the tracks which are going to be updated. MFNetDisk sents the list to PC to perform and control the replication.

The replication uses the real 3390 as source disk and all the mirrors of the real as a target disks.

No need to define a virtual device ( using HCD ) for replication because the real disk was defined to MVS as a real device.

In this mode, MFNetDisk never blocks the real (IBM, EMC) 3390 disks. The overhead for the replication is almost zero.

MFNetDisk problems never affect the operation of the real disks using the replication feature.

ReSync is a process which, copy tracks from a Sync mirror to a mirror which needs to be Sync.

After the ReSync operations, the mirrors tracks are equal in both mirrors and the new mirror status becomes Sync.

Net File is a mirror with data in the net.

Net can be MVS or PC host.

The NetFile mirror can be the source mirror or the target mirror depends on the mirror definition.

The default is that the first mirror which is defined to PC Device is the Source mirror.

A Net File mirror can be linked to a remote PC Device, this great feature enables us to recover a PC Device from remote in case of PC failure and to mirror MVS real device to another MVS real device.

Easy and quickly MFNetDisk can replace or copy any real 3390 to another real 3390 in any place in the net without any dependence on the OEM of the 3390 or any distance limitation.

Using the PC Device Replicator Mode the MFNETDISK will ReSync ( and copy ) the source 3390 to the target standard 3390 and create the same sync data in both standard 3390 without the need to stop or delay the operation with the source 3390.

MFNetDisk will ReSync any updated tracks done to the real 3390 source disk, to all the target mirrors defined in the PC Device.

Mirror type PC File is standard Windows NTFS files or Linux files ( ext2 or ext3 ).

PC File data can be on a hard disk or in any storage media, which are connected to the PC (even USB storage key).

Again, 3390 mirror PC file is a regular PC file. A user can use Windows or Linux COPY and PASTE, and when the paste completed, the user has a backup of his real or emulated 3390 disks.

MFNetDisk snapshot backup enables you to backups your real disks and virtual disks in one second. No need to stop your IO activity during the snapshot backup.

The backup data is stored in pc files which are compressed and deduplicated. This saves a lot of pc disks space.

To access the backup data, you do not need to restore the backup data to disk. The backup data itself is ready to be accessed in second in MF as 3390 disks.

Replicator (ASync) PC device

MFNETDISK can mirror any real standard 3390 without degradation in the performance in MVS and without I/O delay. In this mode, all IO requests are sent directly to the real 3390, without blocking the real 3390. Only compressed Invalid Tracks list is sent to the PC to request the PC MFNetDisk to resync the target mirrors of the real 3390.

Emulator (Sync) PC Device

Emulator PC Device enables MFNETDISK to emulate 3390 disks as IBM doing with Shark and EMC doing with Symmetrix.

All IO CCW requests are sent to PC Server to control the 3390 emulations.

This mode ensures that all the mirrors of the device are Sync before sending to MVS end IO status.

MFNetDisk supports both 3390 disk emulation and 3490 tape emulation.

The tape emulation will run the best as MTL. That is a mountable tape library. The mount requests are automatically done by MFNetDisk.

MFNetDisk can manage your scratch tapes using MFNetDisk tape manager or use any external tapes manager, for example, TMM or CA tapes manager or any other tapes manager.

MFNetDisk will store the tape emulation data in PC storage.

MFNetDisk supports unlimited PC and unlimited tapes.

One MFNetDisk job in PC and MF supports a mixture of emulation, tape, disk, and replication.

For disk emulation also CIOD (like IBM PAV) is supported.

MFNetDisk can make unlimited PC backups to any 3390 virtual or real.

MFNETDISK snapshot backup, backups your real and virtual disks to pc files in less than a second.

Snapshot backups can be done to Replicator (real disk replication) or Emulator PC Device.

Each backup, is stored in compressed and deduplicates pc file.

You can use the backup file as a emulated 3390 disks (real or virtual) in one second without the need to restored the backup to disk.

MVS continues to access the source 3390 without delay during the snapshot backup run time.

If disks syncronization among 3390 disks are needed, easily you can do it by use MFNetDisk script which verify that the disks data are Sync and no IO pending for the disks exist, then the backup time will take less than a second and your disks backups will be Sync and the source 3390 disks can be ready to regular RW IO activity without delay with backup to your disks.

When restored disks is required, MFNetDisk enable you without delay , in less than a second, and without the need to restored the disks data, to use your disk backup data as it was restored to disk as a 3390 emulated disks.

A PC backup runs in a PC, and itnever uses MVS CPU cycles.

MVS is able to access the PC Device which has been restored as it was real 3390 disk (IBM, EMC or HDS).

DR is MFNetDisk.

Logically, Having 3390 mirrors in the net is equal to having DR plan.

MVS controls the link between MVS MFNetDisk and MFNetDisk PC 3390 mirrors using the IP parameter. The IP parameter in MVS can point to any MFNetDisk PC with any required 3390 mirror data.

Using the TCP/IP and the MFNETDISK feature to emulate 3390 and the DR MVS site can access the required 3390 disks in no time.

MFNetDisk can read MVS files from PC without the need to access MVS.

Currently, MFNetDisk can use access method of QSAM (all record types, F, V, FB, VB, span and more) for PDS and for PS MVS files.

MFNetDisk will read the logical record for you using its API.

For another access method like VSAM and PDSE and other MFNetDisk will read the BLOCK data and not the logical record.

With MFNetDisk API, accessing the MVS FILES from PC is a reality.

Example :

The API that can read tracks from MVS file is:

ReadMVSFileTrack (string IP, int PC device, string MVSFile, int TT)

Where

TT: the relative track of the MVS File.

IP: The IP of the MFNetDisk PC Server.

PCDevice: The PC Device.

MVSFile: The MVS DSNAME.