Hi wong, AFAIK the 3Com 4210 is Comware 3.10 based (IIRC I wrote about it here).
The 3Com 4210G instead is Comware 5 based (I wrote here). I'm not sure you have 4210 or 4210G.
The 3Com 4500 should be Comware 5 based as the 4210G.
In ANY case, as Alexis wrote above, you shouldn't migrate (by doing a simple and blind "copy and paste") your actual 4500 configuration (or worst, the 4210 configuration) to a newer HPE Comware 5 (or 7) based Switch...instead a complete reconfiguration by hand should be done.
Given that a suggestion would be:
- go to an old used 3Com (HPE rebranded) 4800G (Comware 5 based).
- go to an "entry level" HPE FlexNetwork 5130/5510/5700 (for sure those series are more expensive than an old used and now unsupported 3Com 4500G, 3Com 4500 and 3Com 4210) to benefit from a CLI and Comware 5 or 7.
- move on and go to an HPE OfficeConnect 1920S (Linux, Web Based) or 1950 (Comware 7 but Web Based).
- move on and go to ArubaOS-Switch or ArubaOS-CX based switch series.
In any case you will not be able to perform a "one click" migration...any choice will require you to re-configure by hand (mostly).