Rooting the Iomega iConnect

Iomega iConnect

The Iomega iConnect is a Marvell Kirkwood (ARM) Linux-based NAS device which comes with 4 USB ports, GbE and wireless support (802.11g). The iConnect contains the same processor as the SheevaPlug, has 256MB RAM memory and 512MB flash memory.

Getting console access

The iConnect has a pin header near the Kensington hole using which you can connect to the serial console. See console access.

Installing Debian (to an external USB drive)

Make sure you have console access first (in the future, it will likely be possible to install Debian without opening up the device; in any case, you are probably voiding your warranty anyway by installing custom software). Then, simply follow the instructions for OpenRD on Martin Michlmayr’s website. A problem is that the installer does not recognize the iConnect and thus does not know how to change the thing to boot the kernel. You will have to do this yourself; either use mkimage to create uImage/uInitrd from the Debian kernel/initrd in /boot or use a kernel for the SheevaPlug (available here) without initrd (much easier) which are already in uImage format. Put the kernel on /boot, then go to U-boot and tell it to load the uImage (ext2load command) and then use bootm to boot. Note that you have to set the root partition through the bootargs variable.

If you use a Mac to connect to the serial port, chances are that the menu-based installer does not work (so choose the text-based if you get garbled characters). There are some documented issues with the partition manager in the current installer. Another problem is that OS X will crash if you unplug the USB-to-serial device while a program is still using it. So remember to kill screen or your terminal program before unplugging.

Installing Debian to internal Flash

Install Debian to USB (see above)
Check whether the MTD layout detected by Debian matches the one specified in U-Boot by Iomega (otherwise, change it by setting the mtdparts= parameter at boot time); use cat /proc/mtd, it should say:
```
dev:    size   erasesize  name
mtd0: 000c0000 00020000 "uboot"
mtd1: 00020000 00020000 "env"
mtd2: 00300000 00020000 "zImage"
mtd3: 00300000 00020000 "initrd"
mtd4: 1f400000 00020000 "boot"
```
Make sure that your kernel supports UBIFS and does not need an initrd to boot (i.e. the SheevaPlug kernels at http://sheeva.with-linux.com/sheeva/ work fine; I was told that the stock Debian kernels for Kirkwood can be used too; this kernel of course is already in /boot). UBIFS is faster, better and safer than JFFS2, but JFFS2 will also work fine. If you are compiling your own kernel or want to use one from the SheevaPlug archive, check whether it boots before continuing (to make sure that any problems you encounter are not due to a faulty kernel).
Back up all your mtd partitions (i.e. with nanddump)
Erase mtd2 (flash_eraseall -j /dev/mtd2)
Write kernel to mtd2 (nandwrite -pm /dev/mtd2 uImage; watch out for flash errors; if they occur, redo eraseall+nandwrite)

Create a UBIFS filesystem on /dev/mtd4:

ubiformat /dev/mtd4 -s 512
ubiattach /dev/ubi_ctrl -m 4
ubimkvol /dev/ubi0 -N rootfs -m
mkdir /mnt/mtd
mount -t ubifs ubi0:rootfs /mnt/mtd

Mount the root partition without /proc and /sys to copy it to the UBI filesystem:
```
mkdir /tmp/root
sync
mount -o bind / /tmp/root
cd /tmp/root
cp -rf ./ /mnt/mtd
```
. This copies your root filesystem to the UBIFS. UBI can compress stuff so if your root partition is larger than 512MB, it will work (up to 700MB I think will do).
Change /mnt/mtd/etc/fstab to make the root partition mount: add
```
/dev/root	/	ubifs	defaults,noatime,rw	0	0
```
as first line
umount /tmp/root, shutdown -r now

Change boot parameters in U-boot so that the kernel is loaded from NAND:

setenv bootcmd_nand 'nand read.e 0x2000000 0x100000 0x300000'
setenv bootcmd 'run bootcmd_nand; bootm'
setenv bootargs 'console=ttyS0,115200 mtdparts=orion_nand:0xc0000@0x0(uboot),0x20000@0xa0000(env),0x300000@0x100000(zImage),0x300000@0x540000(initrd),0x1f400000@0x980000(boot) ubi.mtd=2 root=ubi0:rootfs rootfstype=ubifs'

Try to boot this way; if it works, use saveenv to save this as the default

It’s probably easier and faster to just use debootstrap or something else to create the UBIFS partition and then copy it to the NAND (due to slow write speeds of most USB sticks, installation can take an hour or two). Also, the menu-based Debian installer did not work over the USB serial connection, so I had to use the text-based one. There are also some known problems with the partition manager but that’s all documented at Martin Michlmayr‘s site.

Getting root access to the factory-installed Linux installation

Connect the iConnect to the network (by cable if you have not set it up yet)
Go to http://storage.local./support.html (substitute ‘storage’ with the name you gave the device if you have already set it up – ‘storage’ is the default name)
Set an administrator password
Enable support access (SSH)
Restart the device
Log-in to the device (ssh root@storage.local); the password is “soho”+ your admin password (if your password is ‘foo’, the the password you need to use for ssh is ‘sohofoo’).

Note that the default software (which is a flavour of Debian) is not very suitable to install custom applications on, since the filesystems are contained in an image that is mounted through a loopback (and thus have very little free space). Using console access, it is probably possible to install your own OS.

Device information

This is on a brand new iConnect (with factory-installed Linux):

df –si

Filesystem             Size   Used  Avail Use% Mounted on
rootfs                  53M   4.5M    48M   9% /
/dev/root.old          4.9M   2.0M   2.7M  43% /initrd
none                    53M   4.5M    48M   9% /
ubi0:boot              478M   125M   348M  27% /boot
/dev/loop0             279M   279M      0 100% /mnt/apps
/dev/loop1             5.1M   1.5M   3.4M  31% /etc
/dev/loop2              62k    62k      0 100% /oem
tmpfs                  131M      0   131M   0% /mnt/apps/lib/init/rw
tmpfs                  131M      0   131M   0% /dev/shm

cat /proc/cpuinfo (the CPU is clocked at 1GHz, whereas the SheevaPlug is clocked at 1.2GHz)

Processor	: Feroceon 88FR131 rev 1 (v5l)
BogoMIPS	: 992.87
Features	: swp half thumb fastmult edsp 
CPU implementer	: 0x56
CPU architecture: 5TE
CPU variant	: 0x2
CPU part	: 0x131
CPU revision	: 1

Hardware	: Marvell RD-88F6281 Reference Board
Revision	: 0000
Serial		: 0000000000000000

dmesg