peer is not added if it's down while you restart

[michielbdejong]

Peers are only added at startup or when the admin opens the peers list. If a peer is temporarily down, it should try to connect to it periodically, so that route broadcasts can be resumed once the peer comes back up.

Adding the 'bug' label because this issue will affect network quality.

[michielbdejong]

continued in interledgerjs/ilp-connector#357

[michielbdejong]

we think this is fixed, but let's keep this issue open to remind ourselves to try this out next time we do an ilp-kit release.

[michielbdejong]

(and also check that routes come back up if one ilp-kit restarts but the others don't)