Internal HDD (APA & exFAT)

RiptOPL supports two completely different ways to use the PS2's internal ATA/IDE hard drive: the traditional APA/PFS partition scheme (HDLoader format, used by HDL-Dump and virtually all legacy tools), and the modern exFAT filesystem routed through the Block Device Manager (BDMAssault). Both formats are supported, but you must choose one per boot — they are mutually exclusive in RiptOPL: enabling APA/PFS HDD mode greys out the exFAT BDM HDD toggle, and vice versa. Only 48-bit LBA drives are supported; that covers every IDE drive manufactured after ~2003 and all CF-to-IDE adapters.

ℹ Which format should I use?

APA/PFS is the classic choice: maximum compatibility with every existing tool (HDL-Dump, uLaunchELF, ps2-packer, etc.) and the format your existing HDLoader library already lives on. exFAT is the modern choice: copy ISOs from any PC with no special software, GPT for drives larger than 2 TB, and PS1 VCD support on the same drive — but files must be written contiguously (see the fragmentation warning below). Most users with an existing HDD library should stay on APA/PFS. New builds or large (>2 TB) drives are where exFAT shines.

APA / PFS (HDLoader format)

The APA partition scheme and PFS filesystem are the native PS2 HDD formats, understood by every classic HDD tool. OPL reads games in the HDLoader format — each game occupies one or more APA partitions written by HDL-Dump (or the older HDL server). This path is mature, well-tested, and requires no configuration beyond enabling HDD mode.

Capacity

APA/PFS supports up to 2 TB via 48-bit LBA. Drives larger than 2 TB are not addressable in this format — use exFAT with a GPT partition table instead (see below).

The OPL data partition

OPL stores its data files (artwork, themes, VMCs, configs, cheats, etc.) in a dedicated PFS partition. On first launch, if no partition is found, OPL creates a 128 MB +OPL partition automatically. The partition name can be overridden by placing a config file on the drive before OPL first runs:

hdd0:__common:pfs:OPL/conf_hdd.cfg

That file is an OPL config with a single key:

hdd_partition=__common

The value is the APA partition name (without the hdd0: prefix). If the file is absent OPL writes conf_hdd.cfg into hdd0:__common (at pfs0:OPL/conf_hdd.cfg) recording hdd_partition=+OPL, then creates and mounts hdd0:+OPL as the data partition. The OPL folder tree (CFG/, ART/, VMC/, THM/, etc.) lives inside that partition under pfs0:OPL/.

ℹ Don't enlarge OPL partitions with a hex editor

Resizing an APA partition in place breaks LBA offsets for partitions that follow it on disk, which can corrupt your entire game library. If you need a larger OPL partition, delete the existing one and recreate it at the desired size with uLaunchELF, then copy your data back.

Folder layout

Unlike folder-based devices (USB, MMCE, SMB…), APA/PFS stores games as HDLoader partitions — there are no CD/ or DVD/ folders. All other OPL support files live inside the OPL data partition:

Location	Purpose
`hdd0:GAMENAME` (APA partition)	One HDLoader game partition per title
`pfs0:OPL/CFG/`	Per-game config files
`pfs0:OPL/ART/`	Cover art
`pfs0:OPL/VMC/`	Virtual memory card images
`pfs0:OPL/THM/`	Themes
`pfs0:OPL/CHT/`	Cheat files
`pfs0:OPL/APPS/`	Homebrew ELFs
`pfs0:OPL/LNG/`	Language packs

The pfs0: prefix above refers to the mounted OPL data partition — in practice that is hdd0:+OPL (or whatever partition name you configured in conf_hdd.cfg).

Installing games (HDL-Dump / NBD)

OPL does not install games itself — you install them from a PC using HDL-Dump over the network (via OPL's built-in NBD server). The typical workflow:

Start the NBD server on the PS2

In RiptOPL, open the menu and select Start NBD server. The screen updates to "NBD Server running…" once it is ready. OPL must have a configured IP address (static or DHCP).

Connect from your PC

On Linux: sudo nbd-client 192.168.x.x /dev/nbd1 (load the nbd kernel module first with sudo modprobe nbd). On Windows, use the NBD client of your choice. The drive appears as a raw block device to the OS. See the NBD Server page for full client instructions.

Inject the game with HDL-Dump

With the NBD connection active, run:

hdl_dump inject_dvd ps2/nbd "Game Title" ./GAME.ISO

HDL-Dump writes the game directly into a new APA partition on the PS2's HDD. Disconnect the NBD client when done.

Enable HDD mode in RiptOPL

In Device Settings, set HDD (APA) Start Mode to Manual or Auto. On the next boot the game list appears as the HDD Games tab.

Can I use the old HDL server instead of NBD?

No — RiptOPL (like all recent OPL builds) uses the NBD server protocol. The older HDL server is gone. HDL-Dump still works perfectly; only the transport has changed from HDL's proprietary protocol to the open NBD standard. See the NBD Server page for details.

Can I use pfs-shell or a hex editor?

Yes. Because NBD exposes the raw APA disk to your PC, any tool that worked with the drive when it was physically connected will work over NBD — including pfs-shell, partition managers, and hex editors. Be careful: direct APA partition editing can corrupt the drive if done incorrectly.

PS1 games on APA/PFS

PS1 *.VCD files on an APA/PFS HDD live in dedicated __.POPS partitions (named __.POPS, __.POPS0 … __.POPS9). Each partition holds its VCD files at the partition root. Press L3 on the HDD tab to switch to the VCD view and see them listed. See PS1 Games (VCD) for the full VCD workflow.

exFAT via Block Device Manager (BDMA)

RiptOPL can also treat the internal HDD as a plain exFAT mass-storage device, mounted through the same Block Device Manager (BDMAssault / "BDMA") used for exFAT USB drives. Once enabled, the HDD appears in OPL as an "HDD Games" games list with the HDD icon — it occupies one slot in the shared massN: namespace alongside any USB/MX4SIO devices.

Why exFAT?

No special install tools needed — copy ISOs directly from any PC (Windows, macOS, Linux) to the DVD/ or CD/ folder, just like a USB drive.
MBR up to 2 TB, GPT unlimited — if your drive is larger than 2 TB, GPT breaks the APA ceiling.
PS1 VCDs on the same drive — put *.VCD files in the POPS/ folder and they list under L3 VCD view exactly like a USB drive (with the BDMA equip for POPSTARTER — see below).

Formatting and partition table

Format the drive exFAT from your PC before use. Key rules:

Partition table: MBR (up to 2 TB) or GPT (larger drives)
Filesystem: exFAT
Allocation unit size: Default — do not choose a custom cluster size

ℹ Why "Default" allocation unit size?

Windows and macOS format exFAT with a cluster size based on the drive capacity when you leave it at Default. Choosing a custom cluster size (e.g. 32 KB or 128 KB) can produce a layout that the PS2's BDMAssault driver does not read correctly. Stick with Default to stay on the tested path.

Fragmentation warning

The PS2 cannot seek efficiently through fragmented files. Add files one at a time, sequentially, or use a tool that writes files contiguously — do not drag-drop a batch of files simultaneously (most OSes will interleave the writes, fragmenting every file in the batch). If you already have a fragmented drive, defragment it before use or reformat and re-copy.

Enabling BDM HDD in RiptOPL

Enable HDD (GPT/MBR)

Go to Device Settings and enable HDD (GPT/MBR). On the next boot (or scan) the exFAT HDD mounts into the massN: namespace and an HDD Games tab appears in the game list.

Copy your games

On your PC, place PS2 ISO/ZSO files in the DVD/ (for DVD-format discs) or CD/ (for CD-format discs) folder at the drive root — the same layout as USB. Artwork, themes, configs and VMCs go in their usual folders (ART/, THM/, CFG/, VMC/, etc.).

Launch a game

Select the HDD Games tab in RiptOPL and pick a title. The drive mounts as massN: at runtime — the same path as USB — so all per-game settings, cover art lookups and VMC assignments work identically to a USB drive.

Folder layout

The exFAT HDD uses the same folder structure as USB/MMCE/MX4SIO:

Folder	Contents
`DVD/`	PS2 DVD-format game ISOs / ZSOs
`CD/`	PS2 CD-format game ISOs / ZSOs
`POPS/`	PS1 `*.VCD` files + `POPSTARTER.ELF`
`ART/`	Cover art images
`CFG/`	Per-game config files
`VMC/`	Virtual memory card images
`THM/`	Themes
`CHT/`	Cheat files
`APPS/`	Homebrew ELFs

The device prefix at runtime is massN:/ (where N is the BDM slot index assigned at boot). In conf_apps.cfg, use mass: as the device prefix (the same as USB).

PS1 games on exFAT (BDMA equip)

Put your *.VCD files in the drive's POPS/ folder alongside POPSTARTER.ELF. Press L3 on the HDD Games tab to switch to the VCD view.

POPSTARTER's stock driver only reads FAT32. To boot PS1 games from the exFAT HDD, you must equip the HDD (exFAT) BDMA driver modules: go to General Settings, set BDMA Mode to HDD (exFAT) and BDMA Source to Internal HDD (the source identifies your drive by its ata driver and reads its POPS/usbd.irx.ata + POPS/usbhdfsd.irx.ata). RiptOPL copies the correct BDMAssault module pair onto mc?:/POPSTARTER/ for you when you change the setting.

See PS1 Games (VCD) — exFAT BDMA equip for the complete walkthrough, including the BDMA Source setting.

APA/PFS vs. exFAT at a glance

Feature	APA / PFS	exFAT (BDMA)
Max capacity	2 TB (48-bit LBA)	2 TB (MBR) / unlimited (GPT)
Install method	HDL-Dump via NBD server	Copy files from PC (no tools)
PS2 game format	HDLoader partitions	ISO / ZSO in `DVD/` or `CD/`
OPL data location	`pfs0:OPL/` inside the OPL partition	Standard folders at drive root
PS1 VCD support	`__.POPS*` APA partitions	`POPS/` folder + BDMA equip
Fragmentation risk	None (partition-based)	Yes — add files one at a time
Tool ecosystem	HDL-Dump, pfs-shell, uLaunchELF	Any PC file manager
Enable in RiptOPL	Device Settings → HDD (APA) Start Mode	Device Settings → HDD (GPT/MBR)

Notes & limitations

APA/PFS HDD mode and the exFAT BDM HDD are mutually exclusive in RiptOPL — you can enable only one at a time. Enabling one greys the other out in Device Settings, so a given boot uses either APA/PFS or exFAT, never both.
The exFAT HDD mounts as massN: — it shares that namespace with USB/MX4SIO devices. If you have both a USB drive and the exFAT HDD connected, they each occupy a separate massN slot.
Network boot (UDPBD / UDPFS) is mutually exclusive with SMB, but is independent of the local HDD — you can use HDD and network boot at the same time.
On PS3 Backward Compatible units, HDD mode requires CFW with Cobra. See PS3 BC.
ZSO compressed images are supported on exFAT HDD exactly as on USB. See ZSO Format.