I reproduced in a lab with 3 Kamailio servers
``` kamailio_first 127.0.0.101 modparam("dmq", "server_address", "sip:127.0.0.101:5060") modparam("dmq", "notification_address", "sip:127.0.0.103:5060") modparam("dmq", "multi_notify", 1) modparam("dmq", "num_workers", 2) modparam("dmq", "ping_interval", 15)
kamailio_second 127.0.0.102 notification_peer: 127.0.0.103 modparam("dmq", "server_address", "sip:127.0.0.102:5060") modparam("dmq", "notification_address", "sip:127.0.0.103:5060") modparam("dmq", "multi_notify", 1) modparam("dmq", "num_workers", 2) modparam("dmq", "ping_interval", 15)
kamailio_third 127.0.0.103 notification_peer: 127.0.0.101 modparam("dmq", "server_address", "sip:127.0.0.103:5060") modparam("dmq", "notification_address", "sip:127.0.0.101:5060") modparam("dmq", "multi_notify", 1) modparam("dmq", "num_workers", 2) modparam("dmq", "ping_interval", 15) ```
` kamcmd -s /var/run/kamailio_$1/kamailio_ctl dmq.list_nodes | grep -e host -e status -e last -e local | tr '\n' ' ' | sed -e 's/host/\n&/g'`
``` show dmq bus: first host: 127.0.0.102 status: 2 last_notification: 0 local: 0 host: 127.0.0.103 status: 2 last_notification: 0 local: 0 host: 127.0.0.101 status: 2 last_notification: 0 local: 1 show dmq bus: second host: 127.0.0.101 status: 2 last_notification: 0 local: 0 host: 127.0.0.103 status: 2 last_notification: 0 local: 0 host: 127.0.0.102 status: 2 last_notification: 0 local: 1 show dmq bus: third host: 127.0.0.102 status: 2 last_notification: 0 local: 0 host: 127.0.0.101 status: 2 last_notification: 0 local: 0 host: 127.0.0.103 status: 2 last_notification: 0 local: 1 ``` ``` /etc/init.d/kamailio_first stop /etc/init.d/kamailio_third stop
/etc/init.d/kamailio_third start /etc/init.d/kamailio_first start ```
` kamcmd -s /var/run/kamailio_$1/kamailio_ctl dmq.list_nodes | grep -e host -e status -e last -e local | tr '\n' ' ' | sed -e 's/host/\n&/g'` ``` show dmq bus: first host: 127.0.0.103 status: 2 last_notification: 0 local: 0 host: 127.0.0.101 status: 2 last_notification: 0 local: 1 show dmq bus: second host: 127.0.0.101 status: 8 last_notification: 0 local: 0 host: 127.0.0.103 status: 8 last_notification: 0 local: 0 host: 127.0.0.102 status: 2 last_notification: 0 local: 1 show dmq bus: third host: 127.0.0.101 status: 2 last_notification: 0 local: 0 host: 127.0.0.103 status: 2 last_notification: 0 local: 1 ``` The bus will remain broken, I think there is a second scenario that can break.
The notes I took when I found this (I consider this was a limitation not a bug) Why : when Kamailio_third is shutting down, it will send a message to every peers telling them he is now inactive so they will not try to contact him again. once restarted no nodes will contact him because they have an inactive state for him, at this point the only way he can learn about the other nodes is by contacting Kamailio_first, however Kamailio_first will not know about the other nodes.