[SR-Users] periodic could not resolve hostname

Aloha, I'm experiencing this internal DNS problem with Kamailio, can't seem to figure out what's causing it. Maybe someone can help. Essentially, from time to time (one or two times a day) this situation happens, starting with logs: linux kamailio[773]: ERROR: uac [uac_reg.c:1163]: uac_reg_send(): failed to send request for [some-uuid] linux kamailio[773]: ERROR: <core> [core/resolve.c:1730]: sip_hostport2su(): could not resolve hostname: "my.domain.net" linux kamailio[773]: ERROR: tm [ut.h:309]: uri2dst2(): failed to resolve " my.domain.net" linux kamailio[773]: ERROR: tm [uac.c:480]: t_uac_prepare(): no socket found # Do a Kamailio internal DNS lookup, no results found??? root@linux:~# kamcmd dns.lookup a my.domain.net error: 400 - Not found # Do a system DNS lookup. All good. root@linux:~# dig my.domain.net ;; QUESTION SECTION: ;my.domain.net. IN A ;; ANSWER SECTION: my.domain.net. 18000 IN A 192.168.0.1 # Delete internal Kamailio DNS record root@linux:~# kamcmd dns.delete_a my.domain.net # Lookup again right away. It's there, problem fixed. Why?? root@linux:~# kamcmd dns.lookup a my.domain.net { name: my.domain.net type: A size_bytes: 120 reference_counter: 2 permanent: no expires: 7674 last_used: 0 negative_entry: no records: { { rr_idx: 0 rr_ip: 192.168.0.1 rr_permanent: no rr_expires: 7674 } } }