In a Fault Tolerance environment when after a successful failover from secondary to primary SpectroSERVER, when customer restart the primary SS the Landscape appears Down (red) in the spectrum connections for 5-10 minutes then It goes Up (green)
Release : 10.4.1
Component : Spectrum Core / SpectroSERVER
The .hostrc file of primary SpectroSERVER machine contained a line starting with # (like a comment)
natxirvaxxxx
defthwsxxxx
#defthwspxxxx
defthcaxxxx
nascbwdaxxxx
....
Removed that line and a blank line at the end of file and the problem disappeared.
So be sure the .hostrc contains only the hostname of machines, no other lines.