Bug#995242: isc-dhcp-server: omshell returns inconsistent results or segfaults
Nearly all crashes for omshell happen at an instruction pointer ending with ...6dc. Therefore I guess all crashes happen at the same source code location. Unfortunately with just the segfault line it is difficult to find out this source code line. Therefore the kernel emits one line below the segfault line a line showing the surrounding bytes of the crashing instruction (at amd64). Having this line too it is likely possible to find the exact source code line. [1] Example: [13092.694183] omshell[11741]: segfault at ... [13092.694202] Code: 64 ff ff ff c6 05 15 2f 00 ... So maybe you could at least retrieve from the log one "segfault" line with following "Code:" line? Even better would be to get a backtrace of the crash. If this system is systemd based, the simplest might be to install systemd-coredump. With this package such a backtrace is written directly to the journal. Otherwise there are other core-dump-handler available, but the core has to be analyzed separately. Kind regards, Bernhard Thanks for the reply. The problem now is that those systems are not available anymore. I had this issue only on production. When I was testing Debian 11 with DHCPD on a small testing environment (with few dhcp clients) everything was fine. So to recreate the issue, I should clone one of our 2 DHCPDs (that now are running fine from ISC source), remove the source package and reconfigure the Debian package version... and then redeploy one of them on production. And then hope that the other server (the one running with the SRC-pkg version) will be able to do all the work, when the other dhcpd will crash because of omshell. I had a snapshot of the servers with the Debian-dhcpd-pkg, kept for testing purposes, but I had to delete them for disk space management (I kept them for a while, but 6 monts has passed from the issue's opening). I'll try to recreate a similar environment, but I don't know when I will be able to. Thanks for your support. Regards -- __ Andrea Turbiglio Università degli Studi dell’Insubria Centro Sistemi Informativi e Comunicazione Servizio Telecomunicazioni - Gestione Rete Dati di Ateneo Via Valleggio, 11 22100 - COMO tel. +39 031 238 9784 fax +39 031 238 9709 webwww.uninsubria.it mailandrea.turbig...@uninsubria.it mailnetw...@uninsubria.it
Bug#995242: isc-dhcp-server: omshell returns inconsistent results or segfaults
I temporarily switched our servers to the source package version of isc-dhcp-server (4.4.2) and the same issue doesn't happens, so I assume this is a problem with the Debian version of the package. The servers are now running on Debian 11 without issues (the only problematic package in the transition from debian 10 to debian 11 was isc-dhcp-server). -- __ Andrea Turbiglio Università degli Studi dell’Insubria Centro Sistemi Informativi e Comunicazione Servizio Telecomunicazioni - Gestione Rete Dati di Ateneo Via Valleggio, 11 22100 - COMO tel. +39 031 238 9784 fax +39 031 238 9709 web www.uninsubria.it mail andrea.turbig...@uninsubria.it mail netw...@uninsubria.it
Bug#995242: isc-dhcp-server: omshell returns inconsistent results or segfaults
63a6069b000+45000] kern.info-20210925.log.gz:Sep 25 05:47:35 Sep 25 05:47:35 $hostname2 kernel: [68804.784942] omshell[137990]: segfault at 0 ip 56472bca06dc sp 7ffe99eb8b98 error 4 in omshell[56472bc67000+45000] kern.info-20210925.log.gz:Sep 25 06:18:10 Sep 25 06:18:10 $hostname2 kernel: [70639.905566] isc-worker[141620]: segfault at f ip 5603f2b4055d sp 7fa3159bade0 error 4 in omshell[5603f2b09000+45000] kern.info-20210925.log.gz:Sep 25 09:04:25 Sep 25 09:04:25 $hostname2 kernel: [80614.985424] omshell[161240]: segfault at 0 ip 558a78a7a6dc sp 7fff9df4ba38 error 4 in omshell[558a78a41000+45000] kern.info-20210925.log.gz:Sep 25 09:34:25 Sep 25 09:34:25 $hostname2 kernel: [82415.276674] isc-worker[164586]: segfault at f ip 55ef12b0155d sp 7fb4b4cf1de0 error 4 in omshell[55ef12aca000+45000] kern.info-20210925.log.gz:Sep 25 16:09:22 Sep 25 16:09:21 $hostname2 kernel: [106111.475212] omshell[211831]: segfault at 0 ip 560317b156dc sp 7ffdfb021528 error 4 in omshell[560317adc000+45000] kern.info-20210925.log.gz:Sep 25 17:20:22 Sep 25 17:20:22 $hostname2 kernel: [110371.859670] isc-worker[220054]: segfault at f ip 55b63700255d sp 7f4d70571de0 error 4 in omshell[55b636fcb000+45000] kern.info-20210925.log.gz:Sep 25 18:06:07 Sep 25 18:06:07 $hostname2 kernel: [113117.309279] omshell[225562]: segfault at 0 ip 56064acc46dc sp 7fffa83d6298 error 4 in omshell[56064ac8b000+45000] kern.info-20210928.log.gz:Sep 28 11:05:01 Sep 28 11:05:22 $hostname2 kernel: [ 1458.755006] omshell[4604]: segfault at 0 ip 55623cdd06dc sp 7ffd5a2c7c78 error 4 in omshell[55623cd97000+45000] kern.info-20210928.log.gz:Sep 28 14:38:17 Sep 28 14:38:17 $hostname2 kernel: [14233.628306] omshell[52163]: segfault at fcf56f25bf0 ip 7fc656ded717 sp 00007ffe733c09b0 error 4 in libc-2.31.so[7fc656d8c000+14b000] -- __ Andrea Turbiglio Università degli Studi dell’Insubria Centro Sistemi Informativi e Comunicazione Servizio Telecomunicazioni - Gestione Rete Dati di Ateneo Via Valleggio, 11 22100 - COMO tel. +39 031 238 9784 fax +39 031 238 9709 web www.uninsubria.it mail andrea.turbig...@uninsubria.it mail netw...@uninsubria.it