How disappointing that no-one contributed to this bug. There are many pleas for help from people with similar printing problems... and none of them are very conclusive.
I ran a wireshark trace of the LPD protocol exchange between cups and my network printer. The trace was big, but the later stages showed a tcp protocol violation from the host. A quick search turned up only one hit. It also occurs with IPP, but could apply to ANY tcp protocol! http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=478062 This is a linux kernel bug handling tcp timeout recovery. It applies to ALL kernels after 2.6.22, which explains why I also get the problem on feisty. The bug also applies to 2.6.25, so presumably will affect releases newer than hardy. I am sure MANY people are suffering from this problem but don't know where to look for a solution. Here is the suggested bypass... 1. Power-off your printer to totally clear the corrupt job. 2. Clear the printer spool queue. 3. Power-on the printer 4. sudo sysctl -n net.ipv4.tcp_frto and confirm the current value is 2. 5. sudo sysctl -w net.ipv4.tcp_frto=0 (turns the buggy logic off completely) Note: this bypass will not survive system reboots. After that, the printer works just fine with my 2.6.24-19-generic kernel on an old and slow pentium 3 600mHz processor. BUT the bypass doesn't work at all with the 2.6.24-19-rt kernel on my pentium 4 3gHz processor. I then tried the alternative bypass (net.ipv4.tcp_frto=1), but print jobs hung on both systems. I guess the only way to get this problem resolved properly is to join in on the kernel debugging effort.... -- No print output after upgrade to hardy https://bugs.launchpad.net/bugs/225603 You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
