As new ONT types are supported on the E7 platform, those new types require ONT software to be loaded to the E7 in order to be downloaded to the ONTs.
If the E7 detects that it has an ONT type for which there is not an appropriate image uploaded/configured, it will generate a "Missing ONT Images(s)" alarm.
In order to identify which ONT(s) are triggering the alarm (which will subsequently lead you to which image(s) you need to upload to the E7), there is a "show sw-marrooned-onts" command:
E7>show sw-marooned-onts
System version: 2.4.30.1
Vendor ID Model Product Count
-------------------- ---------------- -------------------- ----------
CXNK 844G-1 P0 635
Note that this command is available in release 2.4 and later and the functionality is also available in the WebGUI at the "ONT --> SW Marroned ONTs" level.
This shows that there are 635 844G ONTs which are connected to the system but there is no 844G software loaded to the E7. In order to clear the alarm, download the latest 844G software from Calix and load it to the E7 as documented in the "E7 GPON ONT Upgrade Guide".