From Terminal:
> diskimage register "/Data/haiku-nightly-anyboot.iso"
Registered file as disk device "/dev/disk/virtual/files/21/raw" with ID 21.
>
> diskimage list
ID File Device
-------------------------------------------------------------------------------
21 /Data/haiku-nightly-anyboot.iso/dev/disk/virtual/files/21/raw
>
> mkdir /HAIKU-ISO
> mount "/dev/disk/virtual/files/21/0" /HAIKU-ISO # [..]/0 is the first partition on the .iso
> mkdir /ESP-ISO
> mount "/dev/disk/virtual/files/21/1" /ESP-ISO # [..]/1 -> second partition
>
> unmount /ESP-ISO
> unmount /HAIKU-ISO
>
> diskimage unregister /Data/haiku-nightly-anyboot.iso
Unregistered file disk device for file "/Data/haiku-nightly-anyboot.iso" (ID: 21)The "ID" will vary with usage.
Alternatively, from GUI:
- Open Applications->DriveSetup
- On the top menu, go to: "Disk image -> Register disk image..."
- Select your Haiku .iso file
Now you should be able to see and mount/unmount the partitions inside the .iso from both DriveSetup and from Tracker's Mount menu.