Thanks to Massimiliano's lead. I was able to workaround this bug by replacing /usr/bin/omshell with a freshly compiled version from source. Note that I've only been using my custom version for about 20 minutes, so YMMV.
I really dislike replacing packages with homemade utilities, as it's a pain to maintain. So I chose to simply replace /usr/bin/omshell instead of the whole thing. Here are the steps that I did: ``` systemctl stop isc-dhcp-server curl -OL https://github.com/isc-projects/dhcp/archive/refs/tags/v4_4_3.tar.gz tar zxf v4_4_3.tar.gz cd dhcp-4_4_3 ./configure make # NO make install # Instead, replace the 1 utility that is causing us problems mv /usr/bin/omshell /usr/bin/omshell.bad cp dhcpctl/omshell /usr/bin/omshell ``` I will point out that the default version includes many more libraries then my custom version, and so presumably one of these system libraries is responsible for the bug, as suggested at https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=995242#40 ``` # ldd /usr/bin/omshell linux-vdso.so.1 (0x00007ffc617e4000) libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007f62c6330000) /lib64/ld-linux-x86-64.so.2 (0x00007f62c67fc000) # ldd /usr/bin/omshell.bad linux-vdso.so.1 (0x00007ffe1ebf8000) libirs-export.so.161 => /lib/x86_64-linux-gnu/libirs-export.so.161 (0x00007fe6b1d18000) libdns-export.so.1109 => /lib/x86_64-linux-gnu/libdns-export.so.1109 (0x00007fe6b1ae3000) libisc-export.so.1105 => /lib/x86_64-linux-gnu/libisc-export.so.1105 (0x00007fe6b1a6c000) libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007fe6b187a000) libpthread.so.0 => /lib/x86_64-linux-gnu/libpthread.so.0 (0x00007fe6b1857000) libisccfg-export.so.163 => /lib/x86_64-linux-gnu/libisccfg-export.so.163 (0x00007fe6b1828000) libdl.so.2 => /lib/x86_64-linux-gnu/libdl.so.2 (0x00007fe6b1820000) libcrypto.so.1.1 => /usr/lib/x86_64-linux-gnu/libcrypto.so.1.1 (0x00007fe6b1549000) /lib64/ld-linux-x86-64.so.2 (0x00007fe6b1daa000) ``` I tried recompiling isc-dhcp-4.4.1 from Ubuntu's source, but it had the same exact error. ** Bug watch added: Debian Bug tracker #995242 https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=995242 -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to isc-dhcp in Ubuntu. https://bugs.launchpad.net/bugs/1916931 Title: omshell returns inconsistent results or segfaults Status in isc-dhcp package in Ubuntu: Confirmed Bug description: I have just built a Ubuntu 20.04 server and installed isc-dhcp-server 4.4.1 on it and I am seeing inconsistent returns from omshell. Initially omshell returns data as expected, but when I exit and re-enter omshell connections fail. Here is the initial, working, session: # omshell > server localhost > port 7911 > key omapi_key <the key> > connect obj: <null> > new failover-state obj: failover-state > set name = "dhcp-failover" obj: failover-state name = "dhcp-failover" > open obj: failover-state name = "dhcp-failover" partner-address = c0:9d:e9:76:e9:55:00:00 partner-port = 00:00:02:07 local-address = 10:9d:e9:76:e9:55:00:00 local-port = 00:00:02:07 max-outstanding-updates = 00:00:00:0a mclt = 00:00:01:2c load-balance-max-secs = 00:00:00:03 load-balance-hba = ff:ff:ff:ff:ff:ff:ff:ff:ff:ff:ff:ff:ff:ff:ff:ff:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00 partner-state = 00:00:00:02 local-state = 00:00:00:02 partner-stos = 60:36:d0:68 local-stos = 60:36:8b:3b hierarchy = 00:00:00:01 last-packet-sent = 00:00:00:00 last-timestamp-received = 00:00:00:00 skew = 00:00:00:00 max-response-delay = 00:00:00:3c cur-unacked-updates = 00:00:00:00 Here is what I see when the connect fails. Well, just hangs really. # omshell > server localhost > port 7911 > key omapi_key <the key> > connect And then I hit ctrl-c to break out and tried again: # omshell > server localhost > port 7911 > key omapi_key <the key> > connect Segmentation fault (core dumped) Note, the peer to this server is still running Ubuntu 18.04 with isc-dhcp-server 4.3.5. Running the exact same commands on the peer works reliably. (They are using the same python script to drive omshell.) The DHCP server on the new system appears to be working just fine as reported by omshell on the peer and systemctl. I was curious if the problem could be with the mis-matched versions of isc-dhcp-server so I shutdown isc-dhcp-server on the 18.04 system and get the same results. I also tried using a python script with the pypureomapi module to try and determine if the problem was in omshell or the server. I got very similar results when I attempted to get information about the failover state of the server. Interestingly interrogating the server about host information seems to work just fine. This is a critical bug since I don't see how to fail over a DHCP that is running the isc-dhcp-server on 20.04 without being able to issue omapi commands. I am attaching apport output to this bug report. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/isc-dhcp/+bug/1916931/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : [email protected] Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
