Yes, it's possible. First, you want to install linux. Pop the disc out of your PS2, and into a PC. Back it up if you've got anything on there. Then, throw in knoppix or another liveCD, and partition the PS2 drive. Hypothetical:
You want PS2Gentoo, on a 30GB harddrive, using 5GB and the rest left to any PFS ps2 filesystem.
Create a PC-style MBR on the drive with cfdisk /dev/hdX
Create a 5GB partition. Save it to disk.
Create a linux filesystem (reiserfs3/ext2) in that 5GB using /dev/hdX1 and mkreiserfs or mkfs.ext2
Mount it, copy over then gentoo/blackrhino tar.bz2 and properly extract it.
unmount the partition.
Boot up linux with the RTE, make sure it's set up and works.
Next, use DMS formatter. do NOT overwrite if it asks.
Create a new partition. call it Apps or whatever you want.
Reboot the PS2. boot linux. If it still works, then reboot, and use execftps or something to copy a couple elfs over to +APPS or whatever you named it.
Make sure they run.
Then reboot linux again, and if all is still well there, fire up hdloader and dump a game.
test the game. If it works, reboot, check linux.
if it works, then copy over the RTE disk image using faplink or hdld_svr.elf
Also, to avoid having the RTE stick at INSTALL -- use EXECFTPS to create a folder named BWLINUX
Then create the following empty text files within:
Edit p2lboot.cnf and add this line:
"RedBoot" redboot.elf "" 203 /dev/hda1 "" RedBoot
Edit p2lboot.opt and add these lines:
And copy the attached redboot.elf into the directory as well. (Redboot is completely freely downloadable.)
You'll have to obtain the linux RTE somewhere. Sorry, can't help you there.
Once you have it, however, my instructions should get it to work for you.
The linux directory WILL show up in the browser as Corrupted Data, because you don't have a proper icon file or icon.sys, but the RTE boot will still work.
Edit: here's the link to redboot's site.
If at first you don't suceed, Pull the trigger again.
See bash. See bash run. See bash run GCC. Run, GCC, Run!