My lightning node is unreachable and lightning-rpc': Connection refused
The first error you are seeing might be related to a previous peer that is no longer reachable. The type of the error (Failed to connect 10 socket: Network is unreachable) suggests that it is using a network that is no longer available. This can be because the peer was connected through Tor, or IPv6, and the Tor proxy isn't running anymore, or the network configuration changed and doesn't support IPv6 anymore. It could also be during OS startup that the network device just isn't ready yet, and this is just transient.

Regarding the connection timeout when attempting to connect to another node, it's likely just not online. I went and checked with nmap if the node is online, and it wasn't when I checked:


Starting Nmap 7.60 ( https://nmap.org ) at 2020-06-06 13:47 CEST
Nmap scan report for net-5-95-80-47.cust.vodafonedsl.it (5.95.80.47)
Host is up.

PORT     STATE    SERVICE
9737/tcp filtered unknown

Nmap done: 1 IP address (1 host up) scanned in 2.05 seconds


So that's nothing out of the ordinary. Might I suggest connecting to some other node?

And finally the UNUSUAL plugin-bcli: Could not connect to 'lightning-rpc': Connection refused error is an artifact from the order in which we start up the plugins and the RPC interface: usually plugins are told that we are ready only after the RPC is made available. The bitcoin-backend plugins are a bit special, because they are needed to check whether we are in sync with the bitcoin network and that we can talk to bitcoind. Therefore the bcli plugin starts before the RPC is ready. The error can be safely ignored and we'll make it less verbose soon (see Github Issue #3553).

Disclaimer: I am one of c-lightning's developers.