For various reasons the system itself can't be rebuilt/upgraded but we can do whatever we want with the additional package manager on it.
My Solaris skills and especially knowledge of the free package managers ecosystem is a bit rusty so I don't know what I can actually use while keeping the somewhat oldish base system.
Currently there is pkg-get using some older Blastwave mirror, it has been used to install things such as Apache2, PHP, Python, Nagios. I would like to remove all the old rusty stuff and all of Blastwave, and start fresh with some newer package distribution.
Can the current Blastwave system be used on that snv_121? Is there any better alternative still compatible with that system (eg. OpenCSW or anything else) ?