Nortel Meridian 1 Manual page 266

Table 6-2
Database conversion requirements, NT system upgrade to X11 release 21 (Part 3 of 3)
X11 release
ROM card
required
From To
For converting a release 19 or 20 customer database
(Use conversion procedure beginning on page 6-65)
19,20 21 NTND08
Note: Use the latest software release (e.g., 15.xx) acquired from your Northern Telecom representative. If a
specific issue is indicated (e.g., 15.53 and 15.57), it must be used.
Software required (see note)
Release 21.xx NT system software disk and data cartridge
Upgrade system installation Upgrading to Meridian 1 system options
SL-1 NT system upgrades 6-7