Re: [SR-Users] Kamailio IMS as kubernetes pods

Hi David, Yes that is right, so when you set to ClusterIP:none, it turns the services into a headless services. and the DNS will resolve to a single POD, instead of a group of PODs, and you can reach every POD through the DNS. IPs may change but the DNS will stay fixed when you use Statefullset, as you need a fixed DNS name for the pod. If you use Deployment you get a randomly generated name, which is not what you want. Abdirahman On Thu, 27 Aug 2020 at 08:06, David Villasmil < david.villasmil.work(a)gmail.com&gt; wrote: > Hello Abdirahman, > > Thanks for replying. > > Do you mean if I create a service for the label selector of what’s > running in the pod, but ser ClusterIP: None, when another pod tries to > resolve that service, it will get the actual IP of the running POD? > > > On Wed, 26 Aug 2020 at 18:02, Abdirahman A. Osman < > abdirahman.osm(a)gmail.com&gt; wrote: > >> Hi Pavithra, >> >> Since POD IPs change, you have to rely on DNS records. To have a >> fixed DNS name like >> >> kamailio.kamalio-service.namespace.svc.cluster.local >> >> >> >> for a pod you will have to use StatefullSet, so the pod DNS name >> doesn't change. Also you have to use Services and set it to ClusterIP: >> none, it will turn your pods to headless services and no load balancing is >> involved. and from my understanding you will be able to reach each POD >> directly through the DNS name. >> https://kubernetes.io/docs/concepts/services-networking/service/ >> >> and don't forget to set your /etc/resolv.conf with the kubedns IP >> address. >> >> Abdirahman >> >> >> >> On Wed, 26 Aug 2020 at 12:45, Pavithra Mohanraja < >> pavimohan3004(a)gmail.com&gt; wrote: >> >>> Hi Abdirahman, >>> >>> Do you mean , if I set clusterIP as None, then kubedns server will >>> be pointing to pod ip so that kubedns/coredns will use pod ip for pod >>> communication instead of service IP. >>> >>> >>> Is my understanding correct? From your explanation. >>> >>> If this is the case, pod ip will be changing whenever I launch the >>> pods . How that can be resolved. >>> >>> Could you kindly helo me with this? >>> >>> >>> Thanks, >>> Pavithra >>> >>> On Wed, Aug 26, 2020, 9:26 PM Abdirahman A. Osman < >>> abdirahman.osm(a)gmail.com&gt; wrote: >>> >>>> David, >>>> >>>> >>>> >>>> Assuming those are pod ips. Using services doesn’t work >>>>> >>>>> since the dns name will resolve to a k8s service ip and no the >>>>> actual >>>>> >>>>> pod running the service. >>>>> >>>> >>>> If you set *clusterIP: None* in the services, you will get POD >>>> IP. >>>> >>>> >>>> >>>> >>>> >>>> Abdirahman >>>> >>>> >>>> >>>> On Wed, 26 Aug 2020 at 10:48, Pavithra Mohanraja < >>>> pavimohan3004(a)gmail.com&gt; wrote: >>>> >>>>> Hi, >>>>> Thanks for the answers. >>>>> @David has got my question. >>>>> >>>>> I have a seperate dns server running in my pcscf pod . So in my >>>>> /etc/resolv.conf file , I would be configuring >>>>> nameserver <pcscf pod ip> >>>>> in all other cscf pods as well for communication. >>>>> >>>>> >>>>> >>>>> My question here is how to change the dns server pointing to >>>>> cluster ip so that my domain name for IMS will be pointing to coredns >>>>> itself. It will restrict me from using pod IP since it changes everytime. >>>>> >>>>> >>>>> @David, can you please tell me the last two lines briefly. I did >>>>> not get it.how you configured . You mean to say still you are using pod Ip. >>>>> >>>>> >>>>> On Wed, Aug 26, 2020, 8:02 PM David Villasmil < >>>>> david.villasmil.work(a)gmail.com&gt; wrote: >>>>> >>>>>> I’ve been trying to figure this out as well. >>>>>> I haven’t yet found a way of publishing to kube-dns the pod IP of >>>>>> the running service. >>>>>> >>>>>> I.e.: >>>>>> kamailio.whatever.local on ip 10.0.0.1 >>>>>> Rtpengine.whatever.local on ip 10.0.0.2 >>>>>> Appserver.whatever.local on 10.0.0.3 >>>>>> >>>>>> Assuming those are pod ips. Using services doesn’t work since the >>>>>> dns name will resolve to a k8s service ip and no the actual pod running the >>>>>> service. >>>>>> >>>>>> Assigning IPs hardcoded doesn’t work either since it might change >>>>>> if the docker changes pod. I can have multiple modes on which a service can >>>>>> run, but only one service (kamailio, rtpengine, appserver, etc) will run on >>>>>> a given pod. >>>>>> >>>>>> On Wed, 26 Aug 2020 at 15:18, Abdirahman A. Osman < >>>>>> abdirahman.osm(a)gmail.com&gt; wrote: >>>>>> >>>>>>> Hi >>>>>>> >>>>>>> Pavithra >>>>>>> >>>>>>> >>>>>>> >>>>>>> >>>>>>> >>>>>>> >>>>>>> >>>>>>> >>>>>>> You can use the kubedns/CoreDNS of the kubernetes cluster to >>>>>>> resolve Internal DNS records of the pods.To assign DNS records for each POD >>>>>>> you have to deploy a service and set the ClusterIP: none. and the dns >>>>>>> record will be something like >>>>>>> kamailio.kamalio-service.platform.svc.cluster.local >>>>>>> which is the podname.servicename.namespace.svc.cluster.local >>>>>>> >>>>>>> In the resolve.conf you will put the kubeDNS/CoreDNS IP as the >>>>>>> nameserver. You can set this in the kubernetes manifest file >>>>>>> >>>>>>> dnsPolicy: "None" >>>>>>> dnsConfig: >>>>>>> nameservers: >>>>>>> - 10.34.0.1 ( >>>>>>> >>>>>>> kubeDNS/CoreDNS ) >>>>>>> >>>>>>> >>>>>>> >>>>>>> >>>>>>> Abdirahman >>>>>>> >>>>>>> >>>>>>> >>>>>>> On Tue, 25 Aug 2020 at 15:34, Sergey Safarov < >>>>>>> s.safarov(a)gmail.com&gt; wrote: >>>>>>> >>>>>>>> I am not k8s developer. >>>>>>>> So cannot provide detailed instructions. Just my point of view. >>>>>>>> >>>>>>>> You can look >>>>>>>> https://kubernetes.io/docs/concepts/extend-kubernetes/operator/ >>>>>>>> >>>>>>>> https://www.magalix.com/blog/creating-custom-kubernetes-operators >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> On Tue, Aug 25, 2020 at 7:41 PM Pavithra Mohanraja < >>>>>>>> pavimohan3004(a)gmail.com&gt; wrote: >>>>>>>> >>>>>>>>> Hi, >>>>>>>>> >>>>>>>>> It would be helpful if you could elaborate what has to be done >>>>>>>>> for kubernetes pods when you mention sip ingress >>>>>>>>> >>>>>>>>> >>>>>>>>> Thanks, >>>>>>>>> >>>>>>>>> >>>>>>>>> Pavithra >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> On Tue, Aug 25, 2020, 9:32 PM Sergey Safarov < >>>>>>>>> s.safarov(a)gmail.com&gt; wrote: >>>>>>>>> >>>>>>>>>> Lot of issues with static IP in Kubernetes. >>>>>>>>>> >>>>>>>>>> Looks as need deploy "sip ingress" like "HTTP/HTTPS ingress" >>>>>>>>>> and then route calls to pods. >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> On Tue, Aug 25, 2020 at 4:40 PM Pavithra Mohanraja < >>>>>>>>>> pavimohan3004(a)gmail.com&gt; wrote: >>>>>>>>>> >>>>>>>>>>> Hi, >>>>>>>>>>> >>>>>>>>>>> I am configuring kamailio IMS as kubernetes pods . >>>>>>>>>>> so each component will be configured as separate pod . >>>>>>>>>>> In order to establish a connection between pods , I am >>>>>>>>>>> configuring bind9 dns server in pcscf pod itself. Communication is >>>>>>>>>>> happening via Pod IP address. >>>>>>>>>>> >>>>>>>>>>> Is there any possibility to have the communication using >>>>>>>>>>> cluster IP . If anybody is aware of kubernetes, Please help me in this >>>>>>>>>>> regard. >>>>>>>>>>> >>>>>>>>>>> I have my /etc/resolv.conf file in pods with >>>>>>>>>>> nameserver <clusterIP> >>>>>>>>>>> search <cluster-dns-domain-name> >>>>>>>>>>> >>>>>>>>>>> Please help. >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> Thanks, >>>>>>>>>>> Pavithra >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> _______________________________________________ >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> Kamailio (SER) - Users Mailing List >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> sr-users(a)lists.kamailio.org >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> https://lists.kamailio.org/cgi-bin/mailman/listinfo/sr-users >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>> >>>>>>>>>> _______________________________________________ >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> Kamailio (SER) - Users Mailing List >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> sr-users(a)lists.kamailio.org >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> https://lists.kamailio.org/cgi-bin/mailman/listinfo/sr-users >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> >>>>>>>>> >>>>>>>>> _______________________________________________ >>>>>>>>> >>>>>>>>> >>>>>>>>> Kamailio (SER) - Users Mailing List >>>>>>>>> >>>>>>>>> >>>>>>>>> sr-users(a)lists.kamailio.org >>>>>>>>> >>>>>>>>> >>>>>>>>> https://lists.kamailio.org/cgi-bin/mailman/listinfo/sr-users >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>> >>>>>>>> _______________________________________________ >>>>>>>> >>>>>>>> >>>>>>>> Kamailio (SER) - Users Mailing List >>>>>>>> >>>>>>>> >>>>>>>> sr-users(a)lists.kamailio.org >>>>>>>> >>>>>>>> >>>>>>>> https://lists.kamailio.org/cgi-bin/mailman/listinfo/sr-users >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>> >>>>>>> _______________________________________________ >>>>>>> >>>>>>> Kamailio (SER) - Users Mailing List >>>>>>> >>>>>>> sr-users(a)lists.kamailio.org >>>>>>> >>>>>>> https://lists.kamailio.org/cgi-bin/mailman/listinfo/sr-users >>>>>>> >>>>>>> -- >>>>>> Regards, >>>>>> >>>>>> David Villasmil >>>>>> email: david.villasmil.work(a)gmail.com >>>>>> phone: +34669448337 >>>>>> >>>>>> >>>>>> _______________________________________________ >>>>>> >>>>>> >>>>>> Kamailio (SER) - Users Mailing List >>>>>> >>>>>> >>>>>> sr-users(a)lists.kamailio.org >>>>>> >>>>>> >>>>>> https://lists.kamailio.org/cgi-bin/mailman/listinfo/sr-users >>>>>> >>>>>> >>>>>> >>>>> >>>>> >>>> >>>> >>> >>> >> >> -- > Regards, > > David Villasmil > email: david.villasmil.work(a)gmail.com > phone: +34669448337 > > > --