Our portal is having basemap issues where the loading is slow and partial. Customers are reporting the basemaps are either not available or has missing segments. Later in the day the basemaps load.
So far we checked the firewall and reindexed the portal. Are there any other fixes for this issue?
"Basemap" can mean a lot of things. You can save any web map to your Portal's basemap gallery, referencing layers from any number of different sources. For example, our org has a number of basemaps that come from our own hosted imagery tiles, and their performance depends upon our GIS server machine. Other basemaps, however, make use of ESRI's vector tile sources, and their performance is entirely out of my hands.
Can you can share the URL of the specific basemap services where you're seeing this behavior?