[mythtv-users] One step forward, two steps back - Frontends not woring properly

[Damian]

On 30/04/2016 02:06, Vincent McIntyre wrote:
> On Fri, Apr 29, 2016 at 10:31:59PM +0100, Damian wrote:
> <snip>
>> I ran one of the remote frontends from the command line to see what error
>> messages I was getting while things were freezing, and I got lots of copies
>> of messages like this ...
>>
>> 2016-04-29 21:49:14.102196 I  MythCoreContext::ConnectCommandSocket():
>> Connecting to backend server: 192.168.0.2:6543 (try 1 of 1)
>> 2016-04-29 21:49:21.121452 E  MythSocket(3b91410:68): ReadStringList: Error,
>> timed out after 7000 ms.
>> 2016-04-29 21:49:21.121843 C  Protocol version check failure.
>>             The response to MYTH_PROTO_VERSION was empty.
>>             This happens when the backend is too busy to respond,
>>             or has deadlocked due to bugs or hardware failure.
>> 2016-04-29 21:49:21.122406 W  Backend : gingerserver currently Unreachable.
>> Skipping this one.
>> 2016-04-29 21:49:21.122558 I MythCoreContext::ConnectCommandSocket():
>> Connecting to backend server: 192.168.0.2:6543
> <snip>
>
> and then you said
>> Here's the output from that:
>>
>> $ netstat -tulpn | grep 3306
>> (Not all processes could be identified, non-owned process info
>>  will not be shown, you would have to be root to see it all.)
>> tcp6       0      0 :::3306                 :::* LISTEN      -
>>
>> and with sudo ...
>>
>> sudo netstat -tulpn | grep 3306
>> tcp6       0      0 :::3306                 :::* LISTEN      819/mysqld
>>
>> I'm guessing, from your comments regarding IP addresses, that this isn't
>> right? There are no ip addresses there.
>>
>> Should I post the output of ifcongig, or would that be a stupid security risk
>> to post publicly?
>>
>
> What this shows is mysql is listening on ipv6 but not ipv4.
> First check your /sbin/ifconfig output. Should be safe to post it here,
> it's on an unroutable network. If there is an interface with an IP
> address that is not in 192.168.0.0/24, leave that out.

Thanks Vincent. Here you go ...

$ /sbin/ifconfig
enp2s0    Link encap:Ethernet  HWaddr 00:9c:02:97:55:54
           inet addr:192.168.0.2  Bcast:192.168.0.255  Mask:255.255.255.0
           inet6 addr: fe80::3b9c:8e34:fb44:2847/64 Scope:Link
           UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
           RX packets:3488095 errors:0 dropped:0 overruns:0 frame:0
           TX packets:5707203 errors:0 dropped:0 overruns:0 carrier:0
           collisions:0 txqueuelen:1000
           RX bytes:1009176206 (1.0 GB)  TX bytes:8235960424 (8.2 GB)
           Interrupt:18

lo        Link encap:Local Loopback
           inet addr:127.0.0.1  Mask:255.0.0.0
           inet6 addr: ::1/128 Scope:Host
           UP LOOPBACK RUNNING  MTU:65536  Metric:1
           RX packets:2377579 errors:0 dropped:0 overruns:0 frame:0
           TX packets:2377579 errors:0 dropped:0 overruns:0 carrier:0
           collisions:0 txqueuelen:1
           RX bytes:373000387 (373.0 MB)  TX bytes:373000387 (373.0 MB)


>
> Is your network configured by network-manager or /etc/network/interfaces?
>

I'm not sure what you mean by this. I set up static IP's on my router if 
that helps.


> Other checks to try on the backend, please report pass/fail
> a) ping 192.168.0.2
>     is it pinging (pass) or not responding
>     eg 4 bytes from 192.168.0.2 icmp_seq=1 ttl=64 time=0.021 ms

Pass from the box itself and from the windows machine I'm connecting to 
it with via SSH. I can't check the remote frontends at the moment, but 
I've checked 192.168.0.2/mythweb with both of them before, and that was 
working fine.
>
> b) telnet 192.168.0.2 3306  (then type ^})
>     to pass, should see something like:
That seemed to work on the machine it's self. I can't check the remote 
frontends at the moment.
>
>     Escape character is '^]'.
>     [ 5.5.49-0ubuntu0.14.04.1 9/}MIc8?nlS<o=!-[fkjmysql_native_password
>
>     If you see this instead
>
>     telnet: Unable to connect to remote host: Connection refused
>
>     that's a fail. It means nothing is listening on port tcp/3306
>
> c) repeat a) & b) from one of the frontends
>    If a & b pass but c fails, could be a firewall but there are other
>    possible issues.
>    Please post the ip address of the machine you tested from too.
>
> Vince
>
I'll do this from the frontends as soon as I can.

Thanks again,
Damian