Problems connecting to Calibre and an odd solution

[kaufman]

Ever since I upgraded to version 2.0 of Calibre I've been having a lot of failures when trying to do a wireless connection.

I haven't changed anything in my setup (except for the new version of Calibre) and it was happening on both my home and my work computers.

I have found the following workflow fixes the problem.

First I go into setting and set the specific IP address and port as indicated by Calibre. That always fails, but then I go back in and reset it to the defaults, and it has connected every time.

That's odd, isn't it?

[chaley]

Yes, it is odd. My guess is that calibre v2 is triggering some antivirus program that V1 didn't trigger.

If you send me CC and calibre debug logs I might be able to say more.

[kaufman]

I will. I'm on a Mac, so no auto virus programs.

Edit: Just sent you two logs. One after the first failure, and the second after changing it to something else, failing the connect, and then changing it to the defaults.

[chaley]

There are weird things happening.

First, there seems to be two calibre machines involved, one whose name starts with a G and one whose name starts with an R. I would guess that the 'G' machine is your home machine.

One scenario I see on 2014-08-22:

• 21:58:59: CC attempts to connect to calibre using "automatic". No calibre instance responds
• 22:00:00: CC attempts to connect to the manually-entered IP address 10.0.1.99. That host is not found on the network.
• 22:00:09: again using 10.0.1.99. Fails again.
• 22:01:21: attempt to connect to calibre using automatic. A calibre instance on "G" with IP address 10.0.1.2 responds. CC successfully connects.

The thing that bothers me is that the IP address you manually entered is not the IP address that calibre responds with via automatic connections. Where did you get that IP address? Is it possible that "G" is connected to your network twice?

Another similar scenario on 2014-08-23:

• 12:35:46: successful automatic connect to 10.0.1.2
• 22:42:52: several failed connects
• 22:52:29: failed attempt to connect to manual address 10.0.1.90
• 22:52:42: successful automatic connect to 10.0.1.2.

Something that makes me wonder about your network. CC uses two different techniques to attempt to auto-connect, a broadcast and mDNS (what Apple calls Bonjour). I see mDNS responses from "G" *sometimes*. What is happening to the others? Do you have a very congested network? A complicated cable/wireless setup? Neighbors who might have wireless hubs that interfere with yours? Clearly something on your network is eating those mDNS packets and, frequently, CC's broadcast packets.

Finally, what happens if you manually enter into CC the IP address 10.0.1.2? Do the failures go away?

[kaufman]

Originally Posted by chaley

There are weird things happening.

What's most weird is that it started happening on two different networks at the same time.

Originally Posted by chaley

First, there seems to be two calibre machines involved, one whose name starts with a G and one whose name starts with an R. I would guess that the 'G' machine is your home machine.

Correct. G is my home machine R is my work machine. Thanks for not shaming me by publicly posting my nerdy machine names.

Originally Posted by chaley

There are weird things happening.
The thing that bothers me is that the IP address you manually entered is not the IP address that calibre responds with via automatic connections. Where did you get that IP address? Is it possible that "G" is connected to your network twice?

That's the address that shows up in Calibre when I open the connect/share dropdown. It says "Stop Wireless connection [10.0.1.90 or 10.2.1.2 Port 9090]"

Originally Posted by chaley

Is it possible that "G" is connected to your network twice?

Oops, I had turned on Wifi a couple of days ago when trying to fix the problem. I just turned it off and will send you another debug log.

Originally Posted by chaley

Do you have a very congested network?

Nope. Its not usually congested, and right now I am the only one doing anything on it.

Originally Posted by chaley

A complicated cable/wireless setup?

Not really. Desktop with a wired connection to the router. Phone connects wirelessly. Extender in the front of the house that other computers connect to.

Originally Posted by chaley

Neighbors who might have wireless hubs that interfere with yours?

I guess its possible, but since the started happening at home and at work on the same day, it seems unlikely.

Originally Posted by chaley

Clearly something on your network is eating those mDNS packets and, frequently, CC's broadcast packets.

This would make more sense if it didn't work if I set the address tom something else and then reset it to the default. Why would that fix it.

Originally Posted by chaley

Finally, what happens if you manually enter into CC the IP address 10.0.1.2? Do the failures go away?

They do.

So, If I am getting failures with the default settings and change it to 10.0.1.90 it still fails, but if I change it back to the default, then it works.


And, If I I am getting failures with the default settings and change it to 10.0.1.2 it works.

I sent you another debug log.

[chaley]

That debug log shows a successful automatic connect and then 45 minutes later a failed connect. Clearly nothing changed in CC and in calibre in that 45 minutes, which means the problem must involve something between them. Unfortunately this is a lot of stuff, including Android, MacOS, and your home network.

Given that the problem happens at work and at home, the only thing in common between those places should be the device. Is this true? If so, then we need to look for what changed on the device. Did you install anything on it a few days ago, especially anything that might use networking? If so, what happens if you uninstall it? Was the device OS upgraded in some way?

[kaufman]

That was my thought too. Only the device is in common. No new installs (well, maybe a game or two, but nothing system or network related). No OS upgrade.

Here's a thought. This started happening after a trip to Europe and the Middle East. Is it possible that it had something to do with the fact that the phone was roming on foreign networks for 5 days? I can't imagine how this would do anything, but given that it fails with the default settings and then works with the default settings after I change them and then reset them, I am confused anyhow.

[chaley]

Originally Posted by kaufman

Here's a thought. This started happening after a trip to Europe and the Middle East. Is it possible that it had something to do with the fact that the phone was roming on foreign networks for 5 days? I can't imagine how this would do anything, but given that it fails with the default settings and then works with the default settings after I change them and then reset them, I am confused anyhow.

That would be very weird, but who knows? I know that after roaming my phone will sometimes not connect properly to wifi leaving me stuck on 3G, but CC should see that.

You don't happen to have tethering turned on, do you? That could do all sorts of strange things.

One suggestion: remove any of the WiFi networks you might have accumulated while traveling. Why? No good reason.

Second suggestion: turn off cell data, turn off wifi. Delete your standard home wifi profile. Turn on wifi and recreate that profile. Try a few times to see if default connections work. Turn on cell data and see if things continue to work.

[kaufman]

Tethering is off.

I deleted all of my accumulated wifi profiles except for home/work/mother-in-law/camera.

I then deleted and recreated home and then tried to connect to Calibre and it worked the first time.

Very odd.

[kaufman]

Oops, I forgot I had changed to the specific address and port. When I changed it back to the default, it no longer worked. I have sent you a debug log.

[chaley]

Those debug logs tell me that sometimes calibre answers and sometimes it doesn't. They don't say why, or where the question is being lost.

BTW: another thing to try someday: reboot your home router. Given that the same problem happens at work I doubt that this will fix anything, but it is worth a try.

Have you rebooted your phone? That is also worth a try. So is resetting to factory defaults, but that is such a big hammer that I can't imagine you would want to do it.

Could you also send me a calibre debug log? That would tell me if calibre hears CC and the answer is lost or if calibre doesn't even hear the question. You get calibre debug logs by clicking on the arrow on preferences (or right-clicking) and choosing Start calibre in debug mode (or something like that). You can also start calibre in debug mode from the command line using calibre-debug -g. That is what I always do, just so I have a debug log in case something goes wrong.

[kaufman]

I sent you a Calibre debug log.

I just rebooted my router, and CC connected without changing anything. I'll try the office tomorrow, but its going to be an interesting coincidence if both routers got in a weird state the same day. If it continues to work, thanks for the suggestion and the help.

[chaley]

Originally Posted by kaufman

I sent you a Calibre debug log.

I just rebooted my router, and CC connected without changing anything. I'll try the office tomorrow, but its going to be an interesting coincidence if both routers got in a weird state the same day. If it continues to work, thanks for the suggestion and the help.

That calibre log shows that CC sent a broadcast 7 seconds after calibre started, and it answered that broadcast. Nothing happened next, so either CC didn't receive the answer or it was a content server request. Sixty six seconds after calibre started CC asked again, calibre answered again, and this time CC connected to the wireless device driver.

Does that time sequence say anything to you?

[kaufman]

Yes, it looks like cc didn't receive the first answer, but it did get the second one. Not sure why, but it is working now.

I am happy to keep investigating this with you if you think it's cc issue, but it is looking like it might just be a router in a strange state issue.

[chaley]

Originally Posted by kaufman

Yes, it looks like cc didn't receive the first answer, but it did get the second one. Not sure why, but it is working now.

I am happy to keep investigating this with you if you think it's cc issue, but it is looking like it might just be a router in a strange state issue.

Let me know if it happens again on a net where you have reset the router. It would be nice to understand why CC isn't receiving those packets, but it isn't worth chasing until it happens again consistently.