# Problem creating a cluster with VMs **URL:** \ **Category:** General\ **Created:** [June 4, 2020, 9:21am UTC](https://forums.suse.com/t/problem-creating-a-cluster-with-vms/17636 "2020-06-04T09:21:38Z")\ **Posts on this page:** 2\ **Page:** 1
**Author:** ![Liran](https://avatars.discourse-cdn.com/v4/letter/l/e19adc/32.png) [@Liran](https://forums.suse.com/u/Liran)\ **Post date:** [June 4, 2020, 9:21am UTC](https://forums.suse.com/t/problem-creating-a-cluster-with-vms/17636/1 "2020-06-04T09:21:38Z")
Trying to setup an environment on laptop as close to real life as possible. Host (Laptop) running Centos 8, has two VMs (Ubuntu 20.04). one master one agent. Goal: to have one master server and to add in the future more VMs that act as K8s Nodes. I’ve installed the UI on the **Host** following quick-start command: > sudo docker run -d --restart=unless-stopped -p 80:80 -p 443:443 rancher/rancher using the UI I have tried to setup a new cluster and ran the generated command on the two VMs. referring below just to the master VM. **Problem: No connection between the VMs and the host** alternative 1 : --server localhost 👆 when I use the following docker run command with --server localhost: > sudo docker run -d --privileged --restart=unless-stopped --net=host -v /etc/kubernetes:/etc/kubernetes -v /var/run:/var/run rancher/rancher-agent:v2.4.4 --server [https://localhost](https://localhost) --token tsxgjh2xfcsknlxtjm5blgrrdvchgzdxbrlwk8bvhnxqbr9md4fwq4 --ca-checksum bcbb425e24f4f330321565f85e4f499c7187925efa02548f65f8a3d60843f1ec --etcd --controlplane --worker I get this error: ``` INFO: Arguments: --server https://localhost --token REDACTED --ca-checksum bcbb425e24f4f330321565f85e4f499c7187925efa02548f65f8a3d60843f1ec --etcd --controlplane --worker INFO: Environment: CATTLE_ADDRESS=172.16.101.128 CATTLE_INTERNAL_ADDRESS= CATTLE_NODE_NAME=ubuntu CATTLE_ROLE=,etcd,worker,controlplane CATTLE_SERVER=https://localhost CATTLE_TOKEN=REDACTED INFO: Using resolv.conf: nameserver 172.16.101.2 search localdomain ERROR: https://localhost/ping is not accessible (Failed to connect to localhost port 443: Connection refused) ``` alternative 2 : --server 192.168.122.1 ✌ docker on master VM keeps restarting - probably can’t connect to the management service on host. i have changed the docker run from [https://localhost](https://localhost) to the vibr0 IP address (192.168.122.1). the container log on the master VM show: `time="2020-06-04T05:48:22Z" level=fatal msg="Get https://192.168.122.1: x509: certificate is valid for 127.0.0.1, 172.17.0.2, not 192.168.122.1"` **Host’s interfaces:** ``` [liran@localhost ~]$ ip a 1: lo: mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000 link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 inet 127.0.0.1/8 scope host lo valid_lft forever preferred_lft forever inet6 ::1/128 scope host valid_lft forever preferred_lft forever 2: enp7s0: mtu 1500 qdisc fq_codel state DOWN group default qlen 1000 link/ether f8:75:a4:31:51:b1 brd ff:ff:ff:ff:ff:ff 3: wlp0s20f3: mtu 1500 qdisc noqueue state UP group default qlen 1000 link/ether 4c:1d:96:05:98:1c brd ff:ff:ff:ff:ff:ff inet 10.0.0.5/24 brd 10.0.0.255 scope global dynamic noprefixroute wlp0s20f3 valid_lft 2522sec preferred_lft 2522sec inet6 fe80::595c:2b38:6a3f:ef95/64 scope link noprefixroute valid_lft forever preferred_lft forever 4: vmnet1: mtu 1500 qdisc fq_codel state UNKNOWN group default qlen 1000 link/ether 00:50:56:c0:00:01 brd ff:ff:ff:ff:ff:ff inet 172.16.1.1/24 brd 172.16.1.255 scope global vmnet1 valid_lft forever preferred_lft forever inet6 fe80::250:56ff:fec0:1/64 scope link valid_lft forever preferred_lft forever 5: vmnet8: mtu 1500 qdisc fq_codel state UNKNOWN group default qlen 1000 link/ether 00:50:56:c0:00:08 brd ff:ff:ff:ff:ff:ff inet 172.16.101.1/24 brd 172.16.101.255 scope global vmnet8 valid_lft forever preferred_lft forever inet6 fe80::250:56ff:fec0:8/64 scope link valid_lft forever preferred_lft forever 6: virbr0: mtu 1500 qdisc noqueue state DOWN group default qlen 1000 link/ether 52:54:00:05:78:06 brd ff:ff:ff:ff:ff:ff inet 192.168.122.1/24 brd 192.168.122.255 scope global virbr0 valid_lft forever preferred_lft forever 7: virbr0-nic: mtu 1500 qdisc fq_codel master virbr0 state DOWN group default qlen 1000 link/ether 52:54:00:05:78:06 brd ff:ff:ff:ff:ff:ff 8: docker0: mtu 1500 qdisc noqueue state UP group default link/ether 02:42:d8:f7:59:3f brd ff:ff:ff:ff:ff:ff inet 172.17.0.1/16 brd 172.17.255.255 scope global docker0 valid_lft forever preferred_lft forever inet6 fe80::42:d8ff:fef7:593f/64 scope link valid_lft forever preferred_lft forever 10: veth2ad56f8@if9: mtu 1500 qdisc noqueue master docker0 state UP group default link/ether ce:51:ea:c7:43:6c brd ff:ff:ff:ff:ff:ff link-netnsid 0 inet6 fe80::cc51:eaff:fec7:436c/64 scope link valid_lft forever preferred_lft forever ``` **VM Master:** docker0 - 172.17.0.1 ens33 - 172.16.101.128 ``` liran@ubuntu:~$ ip a 1: lo: mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000 link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 inet 127.0.0.1/8 scope host lo valid_lft forever preferred_lft forever inet6 ::1/128 scope host valid_lft forever preferred_lft forever 2: ens33: mtu 1500 qdisc fq_codel state UP group default qlen 1000 link/ether 00:0c:29:d5:5b:b5 brd ff:ff:ff:ff:ff:ff inet 172.16.101.128/24 brd 172.16.101.255 scope global dynamic noprefixroute ens33 valid_lft 1621sec preferred_lft 1621sec inet6 fe80::f2fb:7d5f:d422:8c3f/64 scope link noprefixroute valid_lft forever preferred_lft forever 3: docker0: mtu 1500 qdisc noqueue state DOWN group default link/ether 02:42:cd:98:a1:ff brd ff:ff:ff:ff:ff:ff inet 172.17.0.1/16 brd 172.17.255.255 scope global docker0 valid_lft forever preferred_lft forever liran@ubuntu:~$ ip route default via 172.16.101.2 dev ens33 proto dhcp metric 100 169.254.0.0/16 dev ens33 scope link metric 1000 172.16.101.0/24 dev ens33 proto kernel scope link src 172.16.101.128 metric 100 172.17.0.0/16 dev docker0 proto kernel scope link src 172.17.0.1 linkdown liran@ubuntu:~$ netstat -rn Kernel IP routing table Destination Gateway Genmask Flags MSS Window irtt Iface 0.0.0.0 172.16.101.2 0.0.0.0 UG 0 0 0 ens33 169.254.0.0 0.0.0.0 255.255.0.0 U 0 0 0 ens33 172.16.101.0 0.0.0.0 255.255.255.0 U 0 0 0 ens33 172.17.0.0 0.0.0.0 255.255.0.0 U 0 0 0 docker0 liran@ubuntu:~$ cat /etc/resolv.conf # This file is managed by man:systemd-resolved(8). Do not edit. # # This is a dynamic resolv.conf file for connecting local clients to the # internal DNS stub resolver of systemd-resolved. This file lists all # configured search domains. # # Run "resolvectl status" to see details about the uplink DNS servers # currently in use. # # Third party programs must not access this file directly, but only through the # symlink at /etc/resolv.conf. To manage man:resolv.conf(5) in a different way, # replace this symlink by a static file or a different symlink. # # See man:systemd-resolved.service(8) for details about the supported modes of # operation for /etc/resolv.conf. nameserver 127.0.0.53 options edns0 search localdomain ``` **IPTABLES** on Host ``` [liran@localhost ~]$ sudo iptables --list [sudo] password for liran: Chain INPUT (policy ACCEPT) target prot opt source destination Chain FORWARD (policy ACCEPT) target prot opt source destination Chain OUTPUT (policy ACCEPT) target prot opt source destination [liran@localhost ~]$ sudo iptables --list Chain INPUT (policy ACCEPT) target prot opt source destination Chain FORWARD (policy ACCEPT) target prot opt source destination Chain OUTPUT (policy ACCEPT) target prot opt source destination ``` on Master VM ``` liran@ubuntu:~$ sudo iptables --list [sudo] password for liran: Chain INPUT (policy ACCEPT) target prot opt source destination Chain FORWARD (policy DROP) target prot opt source destination DOCKER-USER all -- anywhere anywhere DOCKER-ISOLATION-STAGE-1 all -- anywhere anywhere ACCEPT all -- anywhere anywhere ctstate RELATED,ESTABLISHED DOCKER all -- anywhere anywhere ACCEPT all -- anywhere anywhere ACCEPT all -- anywhere anywhere Chain OUTPUT (policy ACCEPT) target prot opt source destination Chain DOCKER (1 references) target prot opt source destination Chain DOCKER-ISOLATION-STAGE-1 (1 references) target prot opt source destination DOCKER-ISOLATION-STAGE-2 all -- anywhere anywhere RETURN all -- anywhere anywhere Chain DOCKER-ISOLATION-STAGE-2 (1 references) target prot opt source destination DROP all -- anywhere anywhere RETURN all -- anywhere anywhere Chain DOCKER-USER (1 references) target prot opt source destination RETURN all -- anywhere anywhere ``` **VM Agent:** docker0 - 172.17.0.1 ens33 - 172.16.101.129 ---
**Author:** ![Liran](https://avatars.discourse-cdn.com/v4/letter/l/e19adc/32.png) [@Liran](https://forums.suse.com/u/Liran)\ **Post date:** [June 9, 2020, 4:11pm UTC](https://forums.suse.com/t/problem-creating-a-cluster-with-vms/17636/2 "2020-06-09T16:11:06Z")
My assumption was wrong - I thought that rancher/rancher was some UI from which I install on one VM the server and on the other VM the agent. the main problem of communicating between the host and it’s internal VM was not solved. I guess there are some configurations to edit first in order to enable this communication. this post can be deleted.