thunderbird & balsa hang sending >1k-byte message unless MTU reduced from 1500 to 1496

[Julian Briggs]

thunderbird hangs sending message > ~1k every time. The size of the message is critical one less character and the message is sent correctly. (Balsa also hangs in same way)

However if I reduce the MTU from 1500 to 1496 (ifconfig eth0 mtu 1496) then the message is sent immediately,

Technical details:

Dell latitude D630
Ubuntu-8.10

julian@biolpc1860:~$ ifconfig eth0
eth0 Link encap:Ethernet HWaddr 00:1c:23:4f:5d:90
          inet addr:192.168.1.33 Bcast:192.168.1.255 Mask:255.255.255.0
          inet6 addr: fe80::21c:23ff:fe4f:5d90/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
          RX packets:2400 errors:0 dropped:0 overruns:0 frame:0
          TX packets:2526 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:1983864 (1.9 MB) TX bytes:456978 (456.9 KB)
          Interrupt:17

julian@biolpc1860:~$ lsb_release -rd
Description: Ubuntu 8.10
Release: 8.10

julian@biolpc1860:~$ lspci
00:00.0 Host bridge: Intel Corporation Mobile PM965/GM965/GL960 Memory Controller Hub (rev 0c)
00:02.0 VGA compatible controller: Intel Corporation Mobile GM965/GL960 Integrated Graphics Controller (rev 0c)
00:02.1 Display controller: Intel Corporation Mobile GM965/GL960 Integrated Graphics Controller (rev 0c)
00:1a.0 USB Controller: Intel Corporation 82801H (ICH8 Family) USB UHCI Controller #4 (rev 02)
00:1a.1 USB Controller: Intel Corporation 82801H (ICH8 Family) USB UHCI Controller #5 (rev 02)
00:1a.7 USB Controller: Intel Corporation 82801H (ICH8 Family) USB2 EHCI Controller #2 (rev 02)
00:1b.0 Audio device: Intel Corporation 82801H (ICH8 Family) HD Audio Controller (rev 02)
00:1c.0 PCI bridge: Intel Corporation 82801H (ICH8 Family) PCI Express Port 1 (rev 02)
00:1c.1 PCI bridge: Intel Corporation 82801H (ICH8 Family) PCI Express Port 2 (rev 02)
00:1c.5 PCI bridge: Intel Corporation 82801H (ICH8 Family) PCI Express Port 6 (rev 02)
00:1d.0 USB Controller: Intel Corporation 82801H (ICH8 Family) USB UHCI Controller #1 (rev 02)
00:1d.1 USB Controller: Intel Corporation 82801H (ICH8 Family) USB UHCI Controller #2 (rev 02)
00:1d.2 USB Controller: Intel Corporation 82801H (ICH8 Family) USB UHCI Controller #3 (rev 02)
00:1d.7 USB Controller: Intel Corporation 82801H (ICH8 Family) USB2 EHCI Controller #1 (rev 02)
00:1e.0 PCI bridge: Intel Corporation 82801 Mobile PCI Bridge (rev f2)
00:1f.0 ISA bridge: Intel Corporation 82801HEM (ICH8M) LPC Interface Controller (rev 02)
00:1f.1 IDE interface: Intel Corporation 82801HBM/HEM (ICH8M/ICH8M-E) IDE Controller (rev 02)
00:1f.2 IDE interface: Intel Corporation 82801HBM/HEM (ICH8M/ICH8M-E) SATA IDE Controller (rev 02)
00:1f.3 SMBus: Intel Corporation 82801H (ICH8 Family) SMBus Controller (rev 02)
03:01.0 CardBus bridge: O2 Micro, Inc. Cardbus bridge (rev 21)
03:01.4 FireWire (IEEE 1394): O2 Micro, Inc. Firewire (IEEE 1394) (rev 02)
09:00.0 Ethernet controller: Broadcom Corporation NetXtreme BCM5755M Gigabit Ethernet PCI Express (rev 02)
0c:00.0 Network controller: Broadcom Corporation BCM4312 802.11b/g (rev 01)
julian@biolpc1860:~$

Thunderbird 2.0.0.21

connecting wired to a Zyxel p660H-D1 router, fireware V3.40(BGI.0) | 05/09/2008

Mar 23 09:59:09 biolpc1860 kernel: [ 0.000000] Linux version 2.6.27-11-generic (buildd@rothera) (gcc version 4.3.2 (Ubuntu 4.3.2-1ubuntu11) ) #1 SMP Thu Jan 29 19:24:39 UTC 2009 (Ubuntu 2.6.27-11.27-generic)

[Julian Briggs (jrcbriggs)]

I should add that the laptop is dual boot Ubuntu/XP. I can send small and large messges from Thunderbird on XP using Thunderbird profile shared between Ubuntu & XP and using the same network card, router, cabling etc. Julian

[Julian Briggs (jrcbriggs)]

I tested on another network (university of York UK). There I can send large messages from Thunderbird under Ubuntu-8.10.

[Przemek K. (azrael)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. We are sorry that we do not always have the capacity to look at all reported bugs in a timely manner.
There have been many changes in Ubuntu since that time you reported the bug and your problem may have been fixed with some of the updates. It would help us a lot if you could test the current Ubuntu development version (10.04). If you can test it, and it is still an issue, we would appreciate if you could upload updated logs by running apport-collect 347636, and any other logs that are relevant for this particular issue.

[Launchpad Janitor (janitor)]

[Expired for mozilla-thunderbird (Ubuntu) because there has been no activity for 60 days.]