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<  Ejabberd mailing list  ~  server doesnt tell about disconnected user
Guest
Posted: Wed Dec 13, 2006 12:27 pm Reply with quote
Guest
hello,

i have noticed a problem in ejabberd-1.1-2 and jabberd-1.4 . When a user
gets disconnected because of network failure - messages sent to the users
are lost without any notification.

user A connected to server doing chat with user B. user B has lost network
connectivity (isp problem, switch problem, iptables OR LAN is disabled).
User A is still sending messages to User B without any notification of
"messages not reaching User B or user B not available". These messages are
lost, they dont even make it to the offline messsages for user B.


Regards,
Syed Farooq Ahmed

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ejabberd@jabber.ru
http://lists.jabber.ru/mailman/listinfo/ejabberd
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Guest
Posted: Wed Dec 13, 2006 12:38 pm Reply with quote
Guest
On 12/13/06, Farooq <farooq@infinilogic.com> wrote:
> hello,
>
> i have noticed a problem in ejabberd-1.1-2 and jabberd-1.4 . When a user
> gets disconnected because of network failure - messages sent to the users
> are lost without any notification.

Jabber protocol does not have any mechanism of reliable message
delivery. It entirely relies on the underlying TCP protocol (which is
unreliable too, by te way).

In case of network failure ejabberd (I guess not only ejabberd) can't
figure it out before some TCP timeout reaches. All messages sent
before that are lost.

--
Sergei Golovan
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ejabberd@jabber.ru
http://lists.jabber.ru/mailman/listinfo/ejabberd
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Guest
Posted: Wed Dec 13, 2006 3:29 pm Reply with quote
Guest
hmm,

cant this be solved by sending a <recipient-unavailable/> message with error
type "wait"
rfc3920 (XMPP core) gives the provision for some error messages. cant they
be used?

In case of loss of network connectivity, sending data on the network would
result in error?

.

--------- Original message --------
From: Sergei Golovan <sgolovan@gmail.com>
To: ejabberd@jabber.ru <ejabberd@jabber.ru>
Subject: Re: [ejabberd] server doesnt tell about disconnected user
Date: 12-13-06 12:39

> On 12/13/06, Farooq wrote:
> hello,
>
> i have noticed a problem in ejabberd-1.1-2 and jabberd-1.4 . When a user
> gets disconnected because of network failure - messages sent to the users
> are lost without any notification.

Jabber protocol does not have any mechanism of reliable message
delivery. It entirely relies on the underlying TCP protocol (which is
unreliable too, by te way).

In case of network failure ejabberd (I guess not only ejabberd) can't
figure it out before some TCP timeout reaches. All messages sent
before that are lost.

--
Sergei Golovan

_______________________________________________
ejabberd mailing list
ejabberd@jabber.ru
http://lists.jabber.ru/mailman/listinfo/ejabberd
Post recived from mailinglist
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Guest
Posted: Wed Dec 13, 2006 3:35 pm Reply with quote
Guest
this topic is well known and widely discussed, one of the things you can try is manipulating tcp_keepalive, if you can read polish (i guess not Sad ) here is something about that on my blog: http://www.planeta.toliman.pl/?p=47

On 12/13/06, Farooq Ahmed <farooq@infinilogic.com (farooq@infinilogic.com)> wrote:
Quote:
hmm,

cant this be solved by sending a <recipient-unavailable/> message with error
type "wait"
rfc3920 (XMPP core) gives the provision for some error messages. cant they
be used?

In case of loss of network connectivity, sending data on the network would
result in error?

.

--------- Original message --------
From: Sergei Golovan <sgolovan@gmail.com (sgolovan@gmail.com)>
To: ejabberd@jabber.ru (ejabberd@jabber.ru) < ejabberd@jabber.ru (ejabberd@jabber.ru)>
Subject: Re: [ejabberd] server doesnt tell about disconnected user
Date: 12-13-06 12:39

> On 12/13/06, Farooq wrote:
> hello,
>
> i have noticed a problem in ejabberd-1.1-2 and jabberd-1.4 . When a user
> gets disconnected because of network failure - messages sent to the users
> are lost without any notification.

Jabber protocol does not have any mechanism of reliable message
delivery. It entirely relies on the underlying TCP protocol (which is
unreliable too, by te way).

In case of network failure ejabberd (I guess not only ejabberd) can't
figure it out before some TCP timeout reaches. All messages sent
before that are lost.

--
Sergei Golovan

_______________________________________________
ejabberd mailing list
ejabberd@jabber.ru (ejabberd@jabber.ru)
http://lists.jabber.ru/mailman/listinfo/ejabberd



--
pozdrawiam,
Zbyszek Żółkiewski
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Guest
Posted: Thu Dec 14, 2006 8:19 am Reply with quote
Guest
means its better to use other protocols for reliable messaging (msn, yahoo,
icq - all provide reliable message delivery).


--------- Original message --------
From: Zbyszek Żółkiewski <zbyszek@toliman.pl>
To: ejabberd@jabber.ru <ejabberd@jabber.ru>
Subject: Re: [ejabberd] server doesnt tell about disconnected user
Date: 12-13-06 15:36

> this topic is well known and widely discussed, one of the things you can
try
> is manipulating tcp_keepalive, if you can read polish (i guess not Sad )
here
> is something about that on my blog: http://www.planeta.toliman.pl/?p=47
>
>
>
> --
> pozdrawiam,
> Zbyszek Żółkiewski
>
>

_______________________________________________
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ejabberd@jabber.ru
http://lists.jabber.ru/mailman/listinfo/ejabberd
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Guest
Posted: Thu Dec 14, 2006 8:35 am Reply with quote
Guest
it is matter of implementing ACK protocol to xmpp via JEPs or by the RFC update (Peter?). There are also (as i remember) custom solutions implemented by server software (not sure right now but wpjabber probably was supporting something like that)

On 12/14/06, Farooq Ahmed <farooq@infinilogic.com (farooq@infinilogic.com)> wrote:
Quote:
means its better to use other protocols for reliable messaging (msn, yahoo,
icq - all provide reliable message delivery).


---------
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Guest
Posted: Thu Dec 14, 2006 6:15 pm Reply with quote
Guest
Hello,
Le 14 d
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Guest
Posted: Thu Dec 14, 2006 6:18 pm Reply with quote
Guest
Hello,
Le 13 d
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