有点混淆
Kubernetes version (use kubectl version):
Client Version: version.Info{Major:"1", Minor:"4", GitVersion:"v1.4.0", GitCommit:"87d9d8d7bc5aa35041a8ddfe3d4b367381112f89", GitTreeState:"clean", BuildDate:"2016-12-12T21:10:52Z", GoVersion:"go1.6.2", Compiler:"gc", Platform:"linux/amd64"}
Server Version: version.Info{Major:"1", Minor:"4", GitVersion:"v1.4.0", GitCommit:"87d9d8d7bc5aa35041a8ddfe3d4b367381112f89", GitTreeState:"clean", BuildDate:"2016-12-12T21:10:52Z", GoVersion:"go1.6.2", Compiler:"gc", Platform:"linux/amd64"}
环境：
AWS, using VPC, all master and 2 nodes under same subnet
RHEL 7.2
Kernel (e.g. uname -a): Linux master.example.com 3.10.0-514.6.2.el7.x86_64 #1 SMP Fri Feb 17 19:21:31 EST 2017 x86_64 x86_64 x86_64 GNU/Linux
Install tools: Install kubernetes as per Redhat guideline using flannel Network
flannel-config.json
{
"Network": "10.20.0.0/16",
"SubnetLen": 24,
"Backend": {
"Type": "vxlan",
"VNI": 1
}
}
Kubernetes Cluster Network : 10.254.0.0/16
其他：发生了什么：我们有Kubernetes群集设置，并具有以下设置
Master: ip-10-52-2-56.ap-northeast-2.compute.internal
Node1: ip-10-52-2-59.ap-northeast-2.compute.internal
Node2: ip-10-52-2-54.ap-northeast-2.compute.internal
主配置详细信息：
[root@master ~]# egrep -v '^#|^$' /etc/etcd/etcd.conf
ETCD_NAME=default
ETCD_DATA_DIR="/var/lib/etcd/default.etcd"
ETCD_LISTEN_PEER_URLS="http://localhost:2380"
ETCD_LISTEN_CLIENT_URLS="http://0.0.0.0:2379"
ETCD_ADVERTISE_CLIENT_URLS="http://0.0.0.0:2379"
[root@master ~]# egrep -v '^#|^$' /etc/kubernetes/config
KUBE_LOGTOSTDERR="--logtostderr=true"
KUBE_LOG_LEVEL="--v=0"
KUBE_ALLOW_PRIV="--allow-privileged=false"
KUBE_MASTER="--master=http://ip-10-52-2-56.ap-northeast-2.compute.internal:8080"
[root@master ~]# egrep -v '^#|^$' /etc/kubernetes/apiserver
KUBE_API_ADDRESS="--address=0.0.0.0"
KUBE_ETCD_SERVERS="--etcd_servers=http://ip-10-52-2-56.ap-northeast-2.compute.internal:2379"
KUBE_SERVICE_ADDRESSES="--service-cluster-ip-range=10.254.0.0/16"
KUBE_ADMISSION_CONTROL="--admission-control=NamespaceLifecycle,NamespaceExists,LimitRanger,SecurityContextDeny,ServiceAccount,ResourceQuota"
KUBE_API_ARGS="--service_account_key_file=/serviceaccount.key""
[root@master ~]# egrep -v '^#|^$' /etc/sysconfig/flanneld
FLANNEL_ETCD="http://ip-10-52-2-56.ap-northeast-2.compute.internal:2379"
FLANNEL_ETCD_KEY="/coreos.com/network"
FLANNEL_OPTIONS="eth0"
Node1/Node2 config details are same as follows:
[root@ip-10-52-2-59 ec2-user]# egrep -v '^$|^#' /etc/kubernetes/config
KUBE_LOGTOSTDERR="--logtostderr=true"
KUBE_LOG_LEVEL="--v=0"
KUBE_ALLOW_PRIV="--allow-privileged=false"
KUBE_MASTER="--master=http://ip-10-52-2-56.ap-northeast-2.compute.internal:8080"
[root@ip-10-52-2-59 ec2-user]# egrep -v '^#|^$' /etc/kubernetes/kubelet
KUBELET_ADDRESS="--address=0.0.0.0"
KUBELET_HOSTNAME="--hostname-override=ip-10-52-2-59.ap-northeast-2.compute.internal"
KUBELET_API_SERVER="--api-servers=http://ip-10-52-2-56.ap-northeast-2.compute.internal:8080"
KUBELET_POD_INFRA_CONTAINER="--pod-infra-container-image=registry.access.redhat.com/rhel7/pod-infrastructure:latest"
KUBELET_ARGS="--cluster-dns=10.254.0.2 --cluster-domain=cluster.local"
[root@ip-10-52-2-59 ec2-user]# grep KUBE_PROXY_ARGS /etc/kubernetes/proxy
KUBE_PROXY_ARGS=""
[root@ip-10-52-2-59 ec2-user]# egrep -v '^#|^$' /etc/sysconfig/flanneld
FLANNEL_ETCD="http://ip-10-52-2-56.ap-northeast-2.compute.internal:2379"
FLANNEL_ETCD_KEY="/coreos.com/network"
FLANNEL_OPTIONS="eth0"
运行Kube DNS如下以下配置：
apiVersion: v1
kind: Service
metadata:
name: kube-dns
namespace: kube-system
labels:
k8s-app: kube-dns
kubernetes.io/cluster-service: "true"
kubernetes.io/name: "KubeDNS"
spec:
selector:
k8s-app: kube-dns
clusterIP: 10.254.0.2
ports:
name: dns
port: 53
protocol: UDP
name: dns-tcp
port: 53
protocol: TCP
apiVersion: v1
kind: ReplicationController
metadata:
labels:
k8s-app: kube-dns
kubernetes.io/cluster-service: "true"
version: v20
name: kube-dns-v20
namespace: kube-system
spec:
replicas: 1
selector:
k8s-app: kube-dns
version: v20
template:
metadata:
labels:
k8s-app: kube-dns
kubernetes.io/cluster-service: "true"
version: v20
spec:
containers:
-
args:
- "--domain=cluster.local"
- "--kube-master-url=http://ip-10-52-2-56.ap-northeast-2.compute.internal:8080"
- "--dns-port=10053"
image: "gcr.io/google_containers/kubedns-amd64:1.9"
livenessProbe:
failureThreshold: 5
httpGet:
path: /healthz
port: 8080
scheme: HTTP
initialDelaySeconds: 60
successThreshold: 1
timeoutSeconds: 5
name: kubedns
ports:
-
containerPort: 10053
name: dns-local
protocol: UDP
-
containerPort: 10053
name: dns-tcp-local
protocol: TCP
readinessProbe:
httpGet:
path: /readiness
port: 8081
scheme: HTTP
initialDelaySeconds: 30
timeoutSeconds: 5
resources:
limits:
cpu: 100m
memory: 500Mi
requests:
cpu: 100m
memory: 500Mi
-
args:
- "--cache-size=1000"
- "--no-resolv"
- "--server=127.0.0.1#10053"
image: "gcr.io/google_containers/kube-dnsmasq-amd64:1.4"
name: dnsmasq
ports:
-
containerPort: 53
name: dns
protocol: UDP
-
containerPort: 53
name: dns-tcp
protocol: TCP
-
args:
- "-cmd=nslookup kubernetes.default.svc.cluster.local 127.0.0.1 >/dev/null && nslookup kubernetes.default.svc.cluster.local 127.0.0.1:10053 >/dev/null"
- "-port=8080"
- "-quiet"
image: "gcr.io/google_containers/exechealthz-amd64:1.2"
name: healthz
ports:
-
containerPort: 8080
protocol: TCP
resources:
limits:
cpu: 10m
memory: 20Mi
requests:
cpu: 10m
memory: 20Mi
dnsPolicy: Default
发生了什么：kubernetes dns在kube-dns pod工作，如果比例kubedns pod在任何地方都无法正常工作（节点）。
在下面的一个DNS POD中，在Node1上运行，响应也来自Node1 Busybox Pod，但Node2 Buskenbox Pod nslookup未响应。
image1
现在，下面有两个DNS POD在Node1和Node2上运行，您可以看到两个Node
的busybox Pod都没有回答image2
在其他一些观察中...
DNS POD大部分时间在172.17 IP系列中，如果我缩放超过4个POD，则在节点2 DNS POD中进行10.20系列IP。
有趣的部分Node2 Pods从10.20系列IP开始。但是Node1 Pods从172.17系列IP开始。
两个节点的某些可持续输出。
[root@ip-10-52-2-54 ec2-user]# iptables-save | grep DNAT
-A KUBE-SEP-3M72SO5X7J6X6TX6 -p tcp -m comment --comment "default/prometheus:prometheus" -m tcp -j DNAT --to-destination 172.17.0.8:9090
-A KUBE-SEP-7SLC3EUJVX23N2X4 -p tcp -m comment --comment "default/zookeeper:" -m tcp -j DNAT --to-destination 172.17.0.4:2181
-A KUBE-SEP-D4NTKJJ3YXXGJARZ -p udp -m comment --comment "kube-system/kube-dns:dns" -m udp -j DNAT --to-destination 172.17.0.10:53
-A KUBE-SEP-EN24FH2N7PLAR6AW -p tcp -m comment --comment "default/kafkacluster:" -m tcp -j DNAT --to-destination 172.17.0.2:9092
-A KUBE-SEP-LCDAFU4UXQHVDQT6 -p tcp -m comment --comment "default/kubernetes:https" -m recent --set --name KUBE-SEP-LCDAFU4UXQHVDQT6 --mask 255.255.255.255 --rsource -m tcp -j DNAT --to-destination 10.52.2.56:6443
-A KUBE-SEP-MX63IHIHS5ZB4347 -p tcp -m comment --comment "default/nodejs4promethus-scraping:" -m tcp -j DNAT --to-destination 172.17.0.6:3000
-A KUBE-SEP-NOI5B75N7ZJAIPJR -p tcp -m comment --comment "default/mongodb-prometheus-exporter:" -m tcp -j DNAT --to-destination 172.17.0.12:9001
-A KUBE-SEP-O6UDQQL3MHGYTSH5 -p tcp -m comment --comment "default/producer:" -m tcp -j DNAT --to-destination 172.17.0.3:8125
-A KUBE-SEP-QO4SWWCV7NMMGPBN -p tcp -m comment --comment "default/kafka-prometheus-jmx:" -m tcp -j DNAT --to-destination 172.17.0.2:7071
-A KUBE-SEP-SVCEI2UVU246H7MW -p tcp -m comment --comment "default/mongodb:" -m tcp -j DNAT --to-destination 172.17.0.12:27017
-A KUBE-SEP-Y4XH6F2KQCY7WQBG -p tcp -m comment --comment "kube-system/kube-dns:dns-tcp" -m tcp -j DNAT --to-destination 172.17.0.10:53
-A KUBE-SEP-ZXXWX3EF7T3W7UNY -p tcp -m comment --comment "default/grafana:" -m tcp -j DNAT --to-destination 172.17.0.9:3000
[root@ip-10-52-2-54 ec2-user]# iptables-save | grep 53
-A KUBE-SEP-D4NTKJJ3YXXGJARZ -p udp -m comment --comment "kube-system/kube-dns:dns" -m udp -j DNAT --to-destination 172.17.0.10:53
-A KUBE-SEP-Y4XH6F2KQCY7WQBG -p tcp -m comment --comment "kube-system/kube-dns:dns-tcp" -m tcp -j DNAT --to-destination 172.17.0.10:53
-A KUBE-SERVICES -d 10.254.0.2/32 -p udp -m comment --comment "kube-system/kube-dns:dns cluster IP" -m udp --dport 53 -j KUBE-SVC-TCOU7JCQXEZGVUNU
-A KUBE-SERVICES -d 10.254.0.2/32 -p tcp -m comment --comment "kube-system/kube-dns:dns-tcp cluster IP" -m tcp --dport 53 -j KUBE-SVC-ERIFXISQEP7F7OF4
---------
[root@ip-10-52-2-59 ec2-user]# iptables-save | grep DNAT
-A KUBE-SEP-3M72SO5X7J6X6TX6 -p tcp -m comment --comment "default/prometheus:prometheus" -m tcp -j DNAT --to-destination 172.17.0.8:9090
-A KUBE-SEP-7SLC3EUJVX23N2X4 -p tcp -m comment --comment "default/zookeeper:" -m tcp -j DNAT --to-destination 172.17.0.4:2181
-A KUBE-SEP-D4NTKJJ3YXXGJARZ -p udp -m comment --comment "kube-system/kube-dns:dns" -m udp -j DNAT --to-destination 172.17.0.10:53
-A KUBE-SEP-EN24FH2N7PLAR6AW -p tcp -m comment --comment "default/kafkacluster:" -m tcp -j DNAT --to-destination 172.17.0.2:9092
-A KUBE-SEP-LCDAFU4UXQHVDQT6 -p tcp -m comment --comment "default/kubernetes:https" -m recent --set --name KUBE-SEP-LCDAFU4UXQHVDQT6 --mask 255.255.255.255 --rsource -m tcp -j DNAT --to-destination 10.52.2.56:6443
-A KUBE-SEP-MX63IHIHS5ZB4347 -p tcp -m comment --comment "default/nodejs4promethus-scraping:" -m tcp -j DNAT --to-destination 172.17.0.6:3000
-A KUBE-SEP-NOI5B75N7ZJAIPJR -p tcp -m comment --comment "default/mongodb-prometheus-exporter:" -m tcp -j DNAT --to-destination 172.17.0.12:9001
-A KUBE-SEP-O6UDQQL3MHGYTSH5 -p tcp -m comment --comment "default/producer:" -m tcp -j DNAT --to-destination 172.17.0.3:8125
-A KUBE-SEP-QO4SWWCV7NMMGPBN -p tcp -m comment --comment "default/kafka-prometheus-jmx:" -m tcp -j DNAT --to-destination 172.17.0.2:7071
-A KUBE-SEP-SVCEI2UVU246H7MW -p tcp -m comment --comment "default/mongodb:" -m tcp -j DNAT --to-destination 172.17.0.12:27017
-A KUBE-SEP-Y4XH6F2KQCY7WQBG -p tcp -m comment --comment "kube-system/kube-dns:dns-tcp" -m tcp -j DNAT --to-destination 172.17.0.10:53
-A KUBE-SEP-ZXXWX3EF7T3W7UNY -p tcp -m comment --comment "default/grafana:" -m tcp -j DNAT --to-destination 172.17.0.9:3000
[root@ip-10-52-2-59 ec2-user]# iptables-save | grep 53
-A KUBE-SEP-D4NTKJJ3YXXGJARZ -p udp -m comment --comment "kube-system/kube-dns:dns" -m udp -j DNAT --to-destination 172.17.0.10:53
-A KUBE-SEP-Y4XH6F2KQCY7WQBG -p tcp -m comment --comment "kube-system/kube-dns:dns-tcp" -m tcp -j DNAT --to-destination 172.17.0.10:53
-A KUBE-SERVICES -d 10.254.0.2/32 -p tcp -m comment --comment "kube-system/kube-dns:dns-tcp cluster IP" -m tcp --dport 53 -j KUBE-SVC-ERIFXISQEP7F7OF4
-A KUBE-SERVICES -d 10.254.0.2/32 -p udp -m comment --comment "kube-system/kube-dns:dns cluster IP" -m udp --dport 53 -j KUBE-SVC-TCOU7JCQXEZGVUNU
Restarted below serviced on both node
for SERVICES in flanneld docker kube-proxy.service kubelet.service; do
systemctl stop $SERVICES
systemctl start $SERVICES
done
Node1: ifconfig
[root@ip-10-52-2-59 ec2-user]# ifconfig
docker0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 172.17.0.1 netmask 255.255.0.0 broadcast 0.0.0.0
inet6 fe80::42:2dff:fe01:c0b0 prefixlen 64 scopeid 0x20<link>
ether 02:42:2d:01:c0:b0 txqueuelen 0 (Ethernet)
RX packets 1718522 bytes 154898857 (147.7 MiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 1704874 bytes 2186333188 (2.0 GiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 9001
inet 10.52.2.59 netmask 255.255.255.224 broadcast 10.52.2.63
inet6 fe80::91:9aff:fe7e:20a7 prefixlen 64 scopeid 0x20<link>
ether 02:91:9a:7e:20:a7 txqueuelen 1000 (Ethernet)
RX packets 2604083 bytes 2208387383 (2.0 GiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 1974861 bytes 593497458 (566.0 MiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
lo: flags=73<UP,LOOPBACK,RUNNING> mtu 65536
inet 127.0.0.1 netmask 255.0.0.0
inet6 ::1 prefixlen 128 scopeid 0x10<host>
loop txqueuelen 1 (Local Loopback)
RX packets 80 bytes 7140 (6.9 KiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 80 bytes 7140 (6.9 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
veth01225a6: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet6 fe80::1034:a8ff:fe79:aba3 prefixlen 64 scopeid 0x20<link>
ether 12:34:a8:79:ab:a3 txqueuelen 0 (Ethernet)
RX packets 1017 bytes 100422 (98.0 KiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 1869 bytes 145519 (142.1 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
veth3079eb6: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet6 fe80::90c2:62ff:fe84:fb53 prefixlen 64 scopeid 0x20<link>
ether 92:c2:62:84:fb:53 txqueuelen 0 (Ethernet)
RX packets 4891 bytes 714845 (698.0 KiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 5127 bytes 829516 (810.0 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
veth3be8c1f: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet6 fe80::c8a5:64ff:fe15:be95 prefixlen 64 scopeid 0x20<link>
ether ca:a5:64:15:be:95 txqueuelen 0 (Ethernet)
RX packets 210 bytes 27750 (27.0 KiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 307 bytes 35118 (34.2 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
veth559a1ab: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet6 fe80::100b:23ff:fe60:3752 prefixlen 64 scopeid 0x20<link>
ether 12:0b:23:60:37:52 txqueuelen 0 (Ethernet)
RX packets 14926 bytes 1931413 (1.8 MiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 14375 bytes 19695295 (18.7 MiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
veth5c05729: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet6 fe80::cca1:4ff:fe5d:14cd prefixlen 64 scopeid 0x20<link>
ether ce:a1:04:5d:14:cd txqueuelen 0 (Ethernet)
RX packets 455 bytes 797963 (779.2 KiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 681 bytes 83904 (81.9 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
veth85ba9a9: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet6 fe80::74ca:90ff:feae:6f4d prefixlen 64 scopeid 0x20<link>
ether 76:ca:90:ae:6f:4d txqueuelen 0 (Ethernet)
RX packets 19 bytes 1404 (1.3 KiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 66 bytes 4568 (4.4 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
vetha069d16: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet6 fe80::accd:eeff:fe21:6eda prefixlen 64 scopeid 0x20<link>
ether ae:cd:ee:21:6e:da txqueuelen 0 (Ethernet)
RX packets 3566 bytes 7353788 (7.0 MiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 2560 bytes 278400 (271.8 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
vetha58e4af: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet6 fe80::6cd2:16ff:fee2:aa59 prefixlen 64 scopeid 0x20<link>
ether 6e:d2:16:e2:aa:59 txqueuelen 0 (Ethernet)
RX packets 779 bytes 62585 (61.1 KiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 1014 bytes 109417 (106.8 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
vethb7bbef5: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet6 fe80::5ce6:6fff:fe31:c3e prefixlen 64 scopeid 0x20<link>
ether 5e:e6:6f:31:0c:3e txqueuelen 0 (Ethernet)
RX packets 589 bytes 55654 (54.3 KiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 573 bytes 74014 (72.2 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
vethbda3e0a: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet6 fe80::9c0a:f2ff:fea5:23a2 prefixlen 64 scopeid 0x20<link>
ether 9e:0a:f2:a5:23:a2 txqueuelen 0 (Ethernet)
RX packets 490 bytes 47064 (45.9 KiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 645 bytes 77464 (75.6 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
vethfc65cc3: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet6 fe80::b854:dcff:feb4:f4ba prefixlen 64 scopeid 0x20<link>
ether ba:54:dc:b4:f4:ba txqueuelen 0 (Ethernet)
RX packets 503 bytes 508251 (496.3 KiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 565 bytes 73145 (71.4 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
Node2 - ifconfig
[root@ip-10-52-2-54 ec2-user]# ifconfig
docker0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 8951
inet 10.20.48.1 netmask 255.255.255.0 broadcast 0.0.0.0
inet6 fe80::42:87ff:fe39:2ef0 prefixlen 64 scopeid 0x20<link>
ether 02:42:87:39:2e:f0 txqueuelen 0 (Ethernet)
RX packets 269123 bytes 22165441 (21.1 MiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 419870 bytes 149980299 (143.0 MiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 9001
inet 10.52.2.54 netmask 255.255.255.224 broadcast 10.52.2.63
inet6 fe80::9a:d8ff:fed3:4cf5 prefixlen 64 scopeid 0x20<link>
ether 02:9a:d8:d3:4c:f5 txqueuelen 1000 (Ethernet)
RX packets 1517512 bytes 938147149 (894.6 MiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 1425156 bytes 1265738472 (1.1 GiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
flannel.1: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 8951
inet 10.20.48.0 netmask 255.255.0.0 broadcast 0.0.0.0
ether 06:69:bf:c6:8a:12 txqueuelen 0 (Ethernet)
RX packets 0 bytes 0 (0.0 B)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 0 bytes 0 (0.0 B)
TX errors 0 dropped 1 overruns 0 carrier 0 collisions 0
lo: flags=73<UP,LOOPBACK,RUNNING> mtu 65536
inet 127.0.0.1 netmask 255.0.0.0
inet6 ::1 prefixlen 128 scopeid 0x10<host>
loop txqueuelen 1 (Local Loopback)
RX packets 106 bytes 8792 (8.5 KiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 106 bytes 8792 (8.5 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
veth9f05785: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 8951
inet6 fe80::d81e:d3ff:fe5e:bade prefixlen 64 scopeid 0x20<link>
ether da:1e:d3:5e:ba:de txqueuelen 0 (Ethernet)
RX packets 31 bytes 2458 (2.4 KiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 37 bytes 4454 (4.3 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
与两个IFCONFIG输出
在Node-1上检查Flanneld进程，flannel.1 node-1中缺少接口，检查/var/log/log/message，并且还比较两个节点flannel配置文件 -/etc/etc/etc/etc/etc/etc/etc/sysconfig/flannel
看起来法兰绒在Node2上未正确运行。您应该检查Pawan已经指出的日志和配置。
另外，您似乎正在使用旧版本的kubernetes。当前版本是1.5，我建议使用此版本。
网中发现的裸金属设置指南往往很快就会过时，甚至是官方的库伯尼特指南。
我建议不要再使用任何这些指南，而是使用（半）自动部署解决方案，例如Kargo（基于Ansible）或KOPS（仅AWS，GO基于）。如果您不想使用这些自动解决方案，则可以尝试使用当前处于Alpha状态但可能已经足够好的Kubeadm。