One instance unlinked and signal cli shows an error

[thlkmoeller]

Hello,

I am using Linux Mint on 3 laptops and I don't have a smartphone. I created an account for Signal with Signal-cli with my mobile number on one of those laptops. Then I linked 3 instances of Signal-Desktop with it, each on one of the laptops. The "main" instance is on one laptop. Unfortunately this laptop I could't use for about 5 weeks. Now I started it again and the Signal-Desktop app shows me, that it is not coupled anymore and that I should repeat the coupling process. But the signal-cli instance, which i used to couple the laptops (on the same laptop), shows me an error now:

"
thl@thl-ThinkPad-X200:~/Downloads/signal-cli-0.7.4/bin$ ./signal-cli listDevices
ERROR App - Error while checking account +49XXXXXXXXXX: javax.net.ssl.SSLHandshakeException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
"

The two other instances of Signal Desktop still work fine.

Do You have any idea, how I can reconnect the 3rd instance? And what happened to signal cli? what is this error and how can i fix it? Can someone please help?

[AsamK]

You need to update signal-cli or replace the certificate store (#1067 (comment))

[thlkmoeller]

Hello again,
since I didn't know, what to do, I did the synchronizing process again, as described in my own answer to another thread:

#1197

The problems are now:

1. when entering ./signal-cli listDevice, I get 4 linked Desktops, although one of them does now actually not exist anymore due to its lost coupling status
2. on the (again) linked desktop app, there are now all messages till 26th of january and all messages beginning on from 15th of march (today). All messages in between are not there. I know, for whatever reason, the other messages are not synchronized.

And 5 questions:

1. How many days the signal desktop app shall be "not online" in order to loose the linked status, as it happened in my case?
2. Wouldn't it have been possible to bring back to life my desktop app, which was listed in the linked devices (so without doing the coupling process from the beginning) ?
3. How can I anyway synchronize now the messages between end of January and middle of march?
4. What about the old linked device in signal-cli, shall I just leave it there or actively remove it ("removeDevice")?
5. That leads to the last question, how can I exactly identify a device? Can I see in Signal desktop, which device it is? In signal-cli I can see only a long device name consisting of letters and numbers. Can I see the device-names, which I actively chose during the coupling process?

[thlkmoeller]

anyone an idea about maybe at least one of the questions...?

[AsamK]

2. It's technically possible to reactivate a linked devices, but Signal-Desktop doesn't support that ...
3. That's not how Signal works, old messages are never synchronized. Only new messages will be shown in Signal-Desktop.
4. You can just remove the old linked devices.
5. The device name is encrypted, you need a newer signal-cli version to see the device-name you chose.

[thlkmoeller]

a late thank you from me :-)
Does anyone have an answer to question 1?

[thlkmoeller]

i guess, i found it myself, by accident.
see here:

signalapp/Signal-Desktop#4328 (comment)