https://bugs.kde.org/show_bug.cgi?id=77862
Michael Kreitzer <[email protected]> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |[email protected] --- Comment #88 from Michael Kreitzer <mrgrim gr1m org> 2010-11-11 17:57:30 --- There are two main issues when it comes to dead connection detection, and both place the burden of dealing with them on the client to some degree so this is a bug for the client if it fails to handle them gracefully. The first issue is detecting dead daemons. The symptoms will be that tcp packets are sent and the proper ACKs returned indicating the connection is fine, but the server does not respond. This is resolved via timeouts as you mentioned. The second is detecting dead connections in protocols where traffic may not be sent or received for long periods of time. This is generally resolved by regular "pings" if the protocol supports it. IMAP has a NOOP command specifically for this. In some cases the connection may be immediately reset by a firewall, router, or the server tcp stack. In other cases a tcp timeout may be required waiting for the ACK in which case a timeout may be issues by the remote end firewall, router, server or the local tcp stack. Both error codes are ICMP so if an ultra paranoid server admin is blocking these on either end the client will may to rely on a client side timeout making this the same issue as the former. I've seen kmail/kio_imap4 not timeout indefinitely hanging on a dead connection. This is one issue this bug has touched. Another is kmail/kio_imap4 will not properly re-establish a connection even when a connection is reset or it otherwise detects a failed connection. I'll get the error dialog mentioning the connection was lost and it will try to reconnect, but I'm never able to browse my mail again after that until I close kmail and manually kill off the hung kio_imap4 processes. Both related issues need to be addressed to correct the central issue this bug report is about. -- Configure bugmail: https://bugs.kde.org/userprefs.cgi?tab=email ------- You are receiving this mail because: ------- You are the assignee for the bug. _______________________________________________ Kdepim-bugs mailing list [email protected] https://mail.kde.org/mailman/listinfo/kdepim-bugs
