There is no Hardware Upgrade Path from a 170 to any other Hardware from IBM.
You could not do 1 step upgrade from V5R1 to V5R4. Upgrade to V5R2 is no gain, V5R2 not supported any longer from IBM. If you have a box with V5R4 the best is just to do Library and IFS transfers to the VvR4 box from the 170 either from Compatible tape or FTP of Save Files. You could do User Profiles
Configs will have to rename resources on most devices User Libraries escept QGPL and Qusrsys, DLO's andUser IFS objects. Then save 170 QGPL and QUSRSYS and restore to V5R4 box as QGPLOLD and QUSROLD and manually copy objects to QGPL and Qusrsys and finish up with RSTAUT.
This really depends on a few things like number of users, disk required, etc. but if you are currently running a 170 you are probably best to skip the used servers and go straight to a new model 520 E4A. The base E4A is 20 or 30 times faster than the 170, with 300GB disks can give you 1.4TB of RAID5 protected usable disk and you can get an LTO4 (1.6TB) internal tape drive. All this at a price that could be less than half what the 170 cost new.
Services to migrate you to the new E4A could run $4,000+ (About 20+ hours).
If done correctly it's pretty painless. If not you could have problems for many days, weeks or even months. Best to have someone with a proven track record to perform this for you.
Here is the basic steps I use to migrate 170's, 270’s, etc. to the new servers:
Bring down the 170 and install an internal LTO2 tape drive I bring with me (The LTO4 drive will read the LTO2 tapes).
Use the LTO2 drive to save QGPL, QUSRSYS, Security and configuration information from the 170.
Bring the new server up, make sure the disk is setup correctly, make sure there is just the LIC load installed.
(QGPL and QUSRSYS show up as *BACKLEVL on Licensed Program list (GO LICPGM Option 10)).
If not I will reload the OS up to this point.
Change most of the System Values (Use existing system information as guide).
Use CHGNETA command to rename new system to reflect the old systems network attributes.
Restore QGPL and QUSRSYS save from the 170 to the LTO2 tape.
Load the rest of the operating and licensed programs.
(This will upgrade the copied QGPL and QUSRSYS to the OS level of the new system.)
Load the latest CUM and Group PTFs.
Save current security data of the new server to save file.
End all subsystems - ENDSBS *ALL *IMMED
Restore the security data from the 170
Restore the new systems security data from the saved copy (Save File previously created).
Restart the system (IPL).
Restore the user data (Libraries, folders and directories) from the 170.
From the system console:
ENDSBS *ALL *IMMED
Restart the system (IPL).
At this point the system is almost ready but there is a bunch of little things to check and fix.
Once we test out the new server and are happy we perform 2 Entire System saves on both servers.
Change the old servers IPs, Name, Netserver configuration, etc. and put it back On-Line in case we want to see something.
Now we put the new server into service.
There may be little things to fix here and there but for the most part it's a one weekend affair.
We find that there are fewer problems if you do this once correctly than once to Test then again for Go-Live.
The old server remains basically intact just in case we need to go back to it but that hasn't happened to me yet.