Hi Aravind, before the backup mechanics there are three decisions that determine whether this is a two hour job or a rebuild.
First, which OS the 9240 will run. It supports both. HPE's QuickSpecs publish separate scale tables: AOS-8 from a minimum of 8.10, and AOS-10 from 10.4, with the Silver and Gold capacity tiers needing 10.6. Stay on AOS-8 and you keep the standalone architecture and this is a controller swap exercise, though your 7030 will need to be on 8.10 or later to match. Go AOS-10 and there is no config restore at all, it's a rebuild, because AOS-10 gateways take their entire configuration from Central via ZTP or Static Activate. There's no HPE supplied AOS-8 to AOS-10 config converter. Budget for the feature deltas too: no internal authentication server, no AAA FastConnect, and radio tuning moves to AirMatch. If you use the controller's internal DB for local or guest users today, sort that out before you commit.
Second, sanity check the platform. A 7030 tops out at 64 APs and roughly 4,096 devices. The 9240 starts at 512 APs and HPE's own datasheet positions it as the 7210, 7220 and 7240XM replacement. If your actual AP count is 7030 scale, it's worth confirming with your SE that the 9240 is really the intended SKU rather than a 9012 or a smaller 9100. The Silver and Gold capacity tiers aren't field upgradeable, so that decision is permanent.
Third, don't plan a blind flash restore across platforms. The 7030 has 8 combo copper and SFP ports. The 9240 has 4 SFP28 ports and no copper at all. Every interface gigabitethernet 0/0/4 through 0/0/7 stanza has no target on the new box, so those VLANs and trunks quietly disappear, and that usually includes your management path. Port channel membership drops from 8 members to a maximum of 4, and you'll need SFP28 capable uplink ports plus the right optics or DACs, which is a real BOM item people forget. Treat the flashbackup as your archive and as the source for certificates and portal pages, but rebuild the interface and VLAN config by hand with console access on standby.
The documented AOS-8 replacement procedure is counter-intuitive, with no reboot and no write memory until the very end. Backup flash on the 7030 and copy it off. Stage the 9240 with basic IP and console setup. Run license add, then do not reboot and do not save the configuration. Run license export to back those up. Copy the flashbackup across and restore flash, still without rebooting. Run license import. Then reload, answering n when it asks to save the configuration. Note that license server reachability is required during a flash restore, and the two controllers must not be on the network at the same time.
On licensing, start well before the window. Keep your Certificate ID, that's what you transfer, and you can stage the transfer on the portal in advance without affecting the running controller. If you restore a flashbackup onto a different serial the licenses simply won't install and TAC has to regenerate them.
Beyond the config itself, capture your certificates and private keys (they generally can't be re-exported from the controller, so make sure you hold the original PFX), captive portal pages, a local-userdb export, the CPSEC whitelist and AP name mappings, your RADIUS and TACACS shared secrets (encrypted in config, so re-enter by hand), and the LMS-IP and backup LMS-IP values baked into your AP system profiles.
Two things worth confirming with HPE before you order: that the 9240 is supported in the AOS-8 standalone role you actually want rather than only as a managed device under a conductor, and the exact 8.10.0.x maintenance release that added 9240 support.