bug#54214: 28.0.91; rcirc failed to report disconnection

bug#54214: 28.0.91; rcirc failed to report disconnection

[Ken Raeburn]

I had a VPN connection go down, over which I had been running one of
three IRC sessions. The rcirc buffers for the channels on that server,
the server buffer, and the *Messages* buffer, gave no indication at all
that there was a problem. No disconnected status in the mode line, no
status messages logged, no reported attempts to reconnect. I only
noticed it when failing to ssh to another host.

Before reconnecting, I did check “M-x list-processes”, and the server
connection for the third IRC server was not present, indicating that
Emacs recognized the TCP connection was gone. After I brought the VPN
back up, “/reconnect” brought the connection back up.


In GNU Emacs 28.0.91 (build 1, x86_64-redhat-linux-gnu, X toolkit, cairo version 1.17.4, Xaw3d scroll bars)
 of 2022-01-11 built on 7efb8fbccc97436880211dbad44871a1
Windowing system distributor 'The X.Org Foundation', version 11.0.12101004
System Description: Fedora Linux 35 (Workstation Edition)

Configured using:
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 LDFLAGS=-Wl,-z,relro
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Configured features:
ACL CAIRO DBUS FREETYPE GIF GLIB GMP GNUTLS GSETTINGS HARFBUZZ JPEG JSON
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Important settings:
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Load-path shadows:
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/home/raeburn/.emacs.d/elpa/p4-20150721.1937/p4 hides /usr/share/emacs/site-lisp/perforce/p4
/home/raeburn/.emacs.d/elpa/transient-20211101.2251/transient hides /usr/share/emacs/28.0.91/lisp/transient

Features:
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bug#54214: 28.0.91; rcirc failed to report disconnection

[Ken Raeburn]

Some more observations:

I’ve had some more disconnections with no indications in the server or
channel buffers or mode lines that I was now disconnected.  (I’ve got
automatic reconnection disabled currently.)

I am using around-advice on the sentinel function to temporarily enable
debugging, so I do get the reason for the sentinel call logged, at
least.  Sometimes it’s “deleted”, sometimes it’s “connection broken by
remote peer”.

As a workaround, I can figure out using C-c C-n what state I’m in.  If
it fails with an error, I’m disconnected; if it returns no names, not
even my own, I’m connected but haven’t rejoined the current channel.  If
I get a list of names, things are okay.  But I have to think to check
explicitly.

I’ve tried using “/reconnect” in the server buffer and in the channel
buffer.  At least sometimes, if I use it in the channel buffer, the
status messages during session establishment go to the channel buffer
instead of the server buffer.  And it seems sort of haphazard whether I
automatically rejoin the various channels or not.

It occurred to me that I should try to see if there’s a correlation
between authentication strategy at session establishment and automatic
channel rejoining, but I haven’t recorded enough of the right info yet.

BTW, regarding authentication strategies, it would help if it were
documented (better?) when I should use a :password entry in
rcirc-server-alist, and when I should use rcirc-authinfo.  Better still,
I’d like it if .authinfo (or .authinfo.pgp, or some other method
intended for private storage) could be used to store the password
instead, regardless of the authentication strategy, instead of requiring
me to keep (parts of) my .emacs file private.

Ken

bug#54214: 28.0.91; rcirc failed to report disconnection

[Philip Kaludercic]

Ken Raeburn <raeburn@redhat.com> writes:

> I had a VPN connection go down, over which I had been running one of
> three IRC sessions. The rcirc buffers for the channels on that server,
> the server buffer, and the *Messages* buffer, gave no indication at all
> that there was a problem. No disconnected status in the mode line, no
> status messages logged, no reported attempts to reconnect. I only
> noticed it when failing to ssh to another host.
>
> Before reconnecting, I did check “M-x list-processes”, and the server
> connection for the third IRC server was not present, indicating that
> Emacs recognized the TCP connection was gone. After I brought the VPN
> back up, “/reconnect” brought the connection back up.

Could you check if this issue still persists after the commit
37bccf19caa6ad245bb4c8adacfb1a1d203d1d2d?  The approach is to take
advantage of the keepalive messages and attempt a reconnect if these
fail.  This seems to have improved the connection quality on my systems.

-- 
	Philip Kaludercic

bug#54214: 28.0.91; rcirc failed to report disconnection

[Sean Whitton]

Hello Philip,

On Wed 20 Apr 2022 at 02:59pm GMT, Philip Kaludercic wrote:

> Ken Raeburn <raeburn@redhat.com> writes:
>
>> I had a VPN connection go down, over which I had been running one of
>> three IRC sessions. The rcirc buffers for the channels on that server,
>> the server buffer, and the *Messages* buffer, gave no indication at all
>> that there was a problem. No disconnected status in the mode line, no
>> status messages logged, no reported attempts to reconnect. I only
>> noticed it when failing to ssh to another host.
>>
>> Before reconnecting, I did check “M-x list-processes”, and the server
>> connection for the third IRC server was not present, indicating that
>> Emacs recognized the TCP connection was gone. After I brought the VPN
>> back up, “/reconnect” brought the connection back up.
>
> Could you check if this issue still persists after the commit
> 37bccf19caa6ad245bb4c8adacfb1a1d203d1d2d?  The approach is to take
> advantage of the keepalive messages and attempt a reconnect if these
> fail.  This seems to have improved the connection quality on my systems.

I regularly have connection issues similar to those described by Ken.
I'm using a build of Emacs recent enough to include 37bccf19ca.

One thing I have noticed is that my unencrypted connection to a private
IRC server does not have these problems.  It is my SSL connection to
OFTC that disconnects without telling me.

Please let me know if you have ideas for some way that I could help debug.

-- 
Sean Whitton