我有
我的工作
我正在试验kube-proxy的iptables模式。我用--proxy_mode=iptables参数启用了它。似乎缺少一些规则：
iptables -t nat -nvL
Chain PREROUTING (policy ACCEPT 8 packets, 459 bytes)
pkts bytes target prot opt in out source destination
2116 120K KUBE-SERVICES all -- * * 0.0.0.0/0 0.0.0.0/0 /* kubernetes service portals */
Chain INPUT (policy ACCEPT 0 packets, 0 bytes)
pkts bytes target prot opt in out source destination
Chain OUTPUT (policy ACCEPT 2 packets, 120 bytes)
pkts bytes target prot opt in out source destination
718 45203 KUBE-SERVICES all -- * * 0.0.0.0/0 0.0.0.0/0 /* kubernetes service portals */
Chain POSTROUTING (policy ACCEPT 5 packets, 339 bytes)
pkts bytes target prot opt in out source destination
0 0 MASQUERADE all -- * * 0.0.0.0/0 0.0.0.0/0 /* kubernetes service traffic requiring SNAT */ mark match 0x4d415351
Chain KUBE-NODEPORTS (1 references)
pkts bytes target prot opt in out source destination
0 0 MARK tcp -- * * 0.0.0.0/0 0.0.0.0/0 /* default/docker-registry-fe:tcp */ tcp dpt:31195 MARK set 0x4d415351
0 0 KUBE-SVC-XZFGDLM7GMJHZHOY tcp -- * * 0.0.0.0/0 0.0.0.0/0 /* default/docker-registry-fe:tcp */ tcp dpt:31195
0 0 MARK tcp -- * * 0.0.0.0/0 0.0.0.0/0 /* mngbox/jumpbox:ssh */ tcp dpt:30873 MARK set 0x4d415351
0 0 KUBE-SVC-GLKZVFIDXOFHLJLC tcp -- * * 0.0.0.0/0 0.0.0.0/0 /* mngbox/jumpbox:ssh */ tcp dpt:30873
Chain KUBE-SEP-5IXMK7UWPGVTWOJ7 (1 references)
pkts bytes target prot opt in out source destination
0 0 MARK all -- * * 10.116.160.8 0.0.0.0/0 /* mngbox/jumpbox:ssh */ MARK set 0x4d415351
0 0 DNAT tcp -- * * 0.0.0.0/0 0.0.0.0/0 /* mngbox/jumpbox:ssh */ tcp to:10.116.160.8:22
Chain KUBE-SEP-BNPLX5HQYOZINWEQ (1 references)
pkts bytes target prot opt in out source destination
0 0 MARK all -- * * 10.116.161.6 0.0.0.0/0 /* kube-system/monitoring-influxdb:api */ MARK set 0x4d415351
0 0 DNAT tcp -- * * 0.0.0.0/0 0.0.0.0/0 /* kube-system/monitoring-influxdb:api */ tcp to:10.116.161.6:8086
Chain KUBE-SEP-CJMHKLXPTJLTE3OP (1 references)
pkts bytes target prot opt in out source destination
0 0 MARK all -- * * 10.116.254.2 0.0.0.0/0 /* default/kubernetes: */ MARK set 0x4d415351
0 0 DNAT tcp -- * * 0.0.0.0/0 0.0.0.0/0 /* default/kubernetes: */ tcp to:10.116.254.2:6443
Chain KUBE-SEP-GSM3BZTEXEBWDXPN (1 references)
pkts bytes target prot opt in out source destination
0 0 MARK all -- * * 10.116.160.7 0.0.0.0/0 /* kube-system/kube-dns:dns */ MARK set 0x4d415351
0 0 DNAT udp -- * * 0.0.0.0/0 0.0.0.0/0 /* kube-system/kube-dns:dns */ udp to:10.116.160.7:53
Chain KUBE-SEP-OAYOAJINXRPUQDA3 (1 references)
pkts bytes target prot opt in out source destination
0 0 MARK all -- * * 10.116.160.7 0.0.0.0/0 /* kube-system/kube-dns:dns-tcp */ MARK set 0x4d415351
0 0 DNAT tcp -- * * 0.0.0.0/0 0.0.0.0/0 /* kube-system/kube-dns:dns-tcp */ tcp to:10.116.160.7:53
Chain KUBE-SEP-PJJZDQNXDGWM7MU6 (1 references)
pkts bytes target prot opt in out source destination
0 0 MARK all -- * * 10.116.160.5 0.0.0.0/0 /* default/docker-registry-fe:tcp */ MARK set 0x4d415351
0 0 DNAT tcp -- * * 0.0.0.0/0 0.0.0.0/0 /* default/docker-registry-fe:tcp */ tcp to:10.116.160.5:443
Chain KUBE-SEP-RWODGLKOVWXGOHUR (1 references)
pkts bytes target prot opt in out source destination
0 0 MARK all -- * * 10.116.161.6 0.0.0.0/0 /* kube-system/monitoring-influxdb:http */ MARK set 0x4d415351
0 0 DNAT tcp -- * * 0.0.0.0/0 0.0.0.0/0 /* kube-system/monitoring-influxdb:http */ tcp to:10.116.161.6:8083
Chain KUBE-SEP-WE3Z7KMHA6KPJWKK (1 references)
pkts bytes target prot opt in out source destination
0 0 MARK all -- * * 10.116.161.6 0.0.0.0/0 /* kube-system/monitoring-grafana: */ MARK set 0x4d415351
0 0 DNAT tcp -- * * 0.0.0.0/0 0.0.0.0/0 /* kube-system/monitoring-grafana: */ tcp to:10.116.161.6:8080
Chain KUBE-SEP-YBQVM4LA4YMMZIWH (1 references)
pkts bytes target prot opt in out source destination
0 0 MARK all -- * * 10.116.161.3 0.0.0.0/0 /* kube-system/monitoring-heapster: */ MARK set 0x4d415351
0 0 DNAT tcp -- * * 0.0.0.0/0 0.0.0.0/0 /* kube-system/monitoring-heapster: */ tcp to:10.116.161.3:8082
Chain KUBE-SEP-YMZS7BLP4Y6MWTX5 (1 references)
pkts bytes target prot opt in out source destination
0 0 MARK all -- * * 10.116.160.9 0.0.0.0/0 /* infra/docker-registry-backend:docker-registry-backend */ MARK set 0x4d415351
0 0 DNAT tcp -- * * 0.0.0.0/0 0.0.0.0/0 /* infra/docker-registry-backend:docker-registry-backend */ tcp to:10.116.160.9:5000
Chain KUBE-SEP-ZDOOYAKDERKR43R3 (1 references)
pkts bytes target prot opt in out source destination
0 0 MARK all -- * * 10.116.160.10 0.0.0.0/0 /* default/kibana-logging: */ MARK set 0x4d415351
0 0 DNAT tcp -- * * 0.0.0.0/0 0.0.0.0/0 /* default/kibana-logging: */ tcp to:10.116.160.10:5601
Chain KUBE-SERVICES (2 references)
pkts bytes target prot opt in out source destination
0 0 KUBE-SVC-JRXTEHDDTAFMSEAS tcp -- * * 0.0.0.0/0 10.116.0.48 /* kube-system/monitoring-grafana: cluster IP */ tcp dpt:80
0 0 KUBE-SVC-CK6HVV5A27TDFNIA tcp -- * * 0.0.0.0/0 10.116.0.188 /* kube-system/monitoring-influxdb:api cluster IP */ tcp dpt:8086
0 0 KUBE-SVC-DKEW3YDJFV3YJLS2 tcp -- * * 0.0.0.0/0 10.116.0.6 /* infra/docker-registry-backend:docker-registry-backend cluster IP */ tcp dpt:5000
0 0 KUBE-SVC-TCOU7JCQXEZGVUNU udp -- * * 0.0.0.0/0 10.116.0.2 /* kube-system/kube-dns:dns cluster IP */ udp dpt:53
0 0 KUBE-SVC-WEHLQ23XZWSA5ZX3 tcp -- * * 0.0.0.0/0 10.116.0.188 /* kube-system/monitoring-influxdb:http cluster IP */ tcp dpt:8083
0 0 KUBE-SVC-XZFGDLM7GMJHZHOY tcp -- * * 0.0.0.0/0 10.116.1.142 /* default/docker-registry-fe:tcp cluster IP */ tcp dpt:443
0 0 MARK tcp -- * * 0.0.0.0/0 10.116.254.3 /* default/docker-registry-fe:tcp external IP */ tcp dpt:443 MARK set 0x4d415351
0 0 KUBE-SVC-XZFGDLM7GMJHZHOY tcp -- * * 0.0.0.0/0 10.116.254.3 /* default/docker-registry-fe:tcp external IP */ tcp dpt:443 PHYSDEV match ! --physdev-is-in ADDRTYPE match src-type !LOCAL
0 0 KUBE-SVC-XZFGDLM7GMJHZHOY tcp -- * * 0.0.0.0/0 10.116.254.3 /* default/docker-registry-fe:tcp external IP */ tcp dpt:443 ADDRTYPE match dst-type LOCAL
0 0 KUBE-SVC-ERIFXISQEP7F7OF4 tcp -- * * 0.0.0.0/0 10.116.0.2 /* kube-system/kube-dns:dns-tcp cluster IP */ tcp dpt:53
0 0 KUBE-SVC-7IHGTXJ4CF2KVXJZ tcp -- * * 0.0.0.0/0 10.116.1.126 /* kube-system/monitoring-heapster: cluster IP */ tcp dpt:80
0 0 KUBE-SVC-GLKZVFIDXOFHLJLC tcp -- * * 0.0.0.0/0 10.116.1.175 /* mngbox/jumpbox:ssh cluster IP */ tcp dpt:2345
0 0 MARK tcp -- * * 0.0.0.0/0 10.116.254.3 /* mngbox/jumpbox:ssh external IP */ tcp dpt:2345 MARK set 0x4d415351
0 0 KUBE-SVC-GLKZVFIDXOFHLJLC tcp -- * * 0.0.0.0/0 10.116.254.3 /* mngbox/jumpbox:ssh external IP */ tcp dpt:2345 PHYSDEV match ! --physdev-is-in ADDRTYPE match src-type !LOCAL
0 0 KUBE-SVC-GLKZVFIDXOFHLJLC tcp -- * * 0.0.0.0/0 10.116.254.3 /* mngbox/jumpbox:ssh external IP */ tcp dpt:2345 ADDRTYPE match dst-type LOCAL
0 0 KUBE-SVC-6N4SJQIF3IX3FORG tcp -- * * 0.0.0.0/0 10.116.0.1 /* default/kubernetes: cluster IP */ tcp dpt:443
0 0 KUBE-SVC-B6ZEWWY2BII6JG2L tcp -- * * 0.0.0.0/0 10.116.0.233 /* default/kibana-logging: cluster IP */ tcp dpt:8888
0 0 MARK tcp -- * * 0.0.0.0/0 10.116.254.3 /* default/kibana-logging: external IP */ tcp dpt:8888 MARK set 0x4d415351
0 0 KUBE-SVC-B6ZEWWY2BII6JG2L tcp -- * * 0.0.0.0/0 10.116.254.3 /* default/kibana-logging: external IP */ tcp dpt:8888 PHYSDEV match ! --physdev-is-in ADDRTYPE match src-type !LOCAL
0 0 KUBE-SVC-B6ZEWWY2BII6JG2L tcp -- * * 0.0.0.0/0 10.116.254.3 /* default/kibana-logging: external IP */ tcp dpt:8888 ADDRTYPE match dst-type LOCAL
0 0 KUBE-NODEPORTS all -- * * 0.0.0.0/0 0.0.0.0/0 /* kubernetes service nodeports; NOTE: this must be the last rule in this chain */ ADDRTYPE match dst-type LOCAL
Chain KUBE-SVC-6N4SJQIF3IX3FORG (1 references)
pkts bytes target prot opt in out source destination
0 0 KUBE-SEP-CJMHKLXPTJLTE3OP all -- * * 0.0.0.0/0 0.0.0.0/0 /* default/kubernetes: */
Chain KUBE-SVC-7IHGTXJ4CF2KVXJZ (1 references)
pkts bytes target prot opt in out source destination
0 0 KUBE-SEP-YBQVM4LA4YMMZIWH all -- * * 0.0.0.0/0 0.0.0.0/0 /* kube-system/monitoring-heapster: */
Chain KUBE-SVC-B6ZEWWY2BII6JG2L (3 references)
pkts bytes target prot opt in out source destination
0 0 KUBE-SEP-ZDOOYAKDERKR43R3 all -- * * 0.0.0.0/0 0.0.0.0/0 /* default/kibana-logging: */
Chain KUBE-SVC-CK6HVV5A27TDFNIA (1 references)
pkts bytes target prot opt in out source destination
0 0 KUBE-SEP-BNPLX5HQYOZINWEQ all -- * * 0.0.0.0/0 0.0.0.0/0 /* kube-system/monitoring-influxdb:api */
Chain KUBE-SVC-DKEW3YDJFV3YJLS2 (1 references)
pkts bytes target prot opt in out source destination
0 0 KUBE-SEP-YMZS7BLP4Y6MWTX5 all -- * * 0.0.0.0/0 0.0.0.0/0 /* infra/docker-registry-backend:docker-registry-backend */
Chain KUBE-SVC-ERIFXISQEP7F7OF4 (1 references)
pkts bytes target prot opt in out source destination
0 0 KUBE-SEP-OAYOAJINXRPUQDA3 all -- * * 0.0.0.0/0 0.0.0.0/0 /* kube-system/kube-dns:dns-tcp */
Chain KUBE-SVC-GLKZVFIDXOFHLJLC (4 references)
pkts bytes target prot opt in out source destination
0 0 KUBE-SEP-5IXMK7UWPGVTWOJ7 all -- * * 0.0.0.0/0 0.0.0.0/0 /* mngbox/jumpbox:ssh */
Chain KUBE-SVC-JRXTEHDDTAFMSEAS (1 references)
pkts bytes target prot opt in out source destination
0 0 KUBE-SEP-WE3Z7KMHA6KPJWKK all -- * * 0.0.0.0/0 0.0.0.0/0 /* kube-system/monitoring-grafana: */
Chain KUBE-SVC-TCOU7JCQXEZGVUNU (1 references)
pkts bytes target prot opt in out source destination
0 0 KUBE-SEP-GSM3BZTEXEBWDXPN all -- * * 0.0.0.0/0 0.0.0.0/0 /* kube-system/kube-dns:dns */
Chain KUBE-SVC-WEHLQ23XZWSA5ZX3 (1 references)
pkts bytes target prot opt in out source destination
0 0 KUBE-SEP-RWODGLKOVWXGOHUR all -- * * 0.0.0.0/0 0.0.0.0/0 /* kube-system/monitoring-influxdb:http */
Chain KUBE-SVC-XZFGDLM7GMJHZHOY (4 references)
pkts bytes target prot opt in out source destination
0 0 KUBE-SEP-PJJZDQNXDGWM7MU6 all -- * * 0.0.0.0/0 0.0.0.0/0 /* default/docker-registry-fe:tcp */
当我向服务ip请求时，在我的情况下它是10.116.0.2我收到了错误
;; connection timed out; no servers could be reached
当我向10.116.160.7服务器请求时，它工作正常。 我可以看到流量根本不是针对kube-proxy规则的，所以可能会遗漏一些东西。
我将非常感谢任何关于缺失规则的提示
修改的 我已经更新了我的初始请求，其中包含了thokin要求的缺失信息，他指出了调试kube-proxy的iptables规则的非常好的方法，我可以用以下方法识别我的问题：
for c in PREROUTING OUTPUT POSTROUTING; do iptables -t nat -I $c -d 10.116.160.7 -j LOG --log-prefix "DBG@$c: "; done
for c in PREROUTING OUTPUT POSTROUTING; do iptables -t nat -I $c -d 10.116.0.2 -j LOG --log-prefix "DBG@$c: "; done
然后我执行了以下命令： #nslookup kubernetes.default.svc.psc01.cluster 10.116.160.7 服务器：10.116.160.7 地址：10.116.160.7＃53
Name: kubernetes.default.svc.psc01.cluster
Address: 10.116.0.1
# nslookup kubernetes.default.svc.psc01.cluster 10.116.0.2
;; connection timed out; no servers could be reached
结果我得到了不同的来源＆＃34;地址和传出接口：
[701768.263847] DBG@OUTPUT: IN= OUT=bond1.300 SRC=10.116.250.252 DST=10.116.0.2 LEN=82 TOS=0x00 PREC=0x00 TTL=64 ID=12436 PROTO=UDP SPT=54501 DPT=53 LEN=62
[702620.454211] DBG@OUTPUT: IN= OUT=docker0 SRC=10.116.176.1 DST=10.116.160.7 LEN=82 TOS=0x00 PREC=0x00 TTL=64 ID=22733 PROTO=UDP SPT=28704 DPT=53 LEN=62
[702620.454224] DBG@POSTROUTING: IN= OUT=docker0 SRC=10.116.176.1 DST=10.116.160.7 LEN=82 TOS=0x00 PREC=0x00 TTL=64 ID=22733 PROTO=UDP SPT=28704 DPT=53 LEN=62
[702626.318258] DBG@OUTPUT: IN= OUT=bond1.300 SRC=10.116.250.252 DST=10.116.0.2 LEN=82 TOS=0x00 PREC=0x00 TTL=64 ID=30608 PROTO=UDP SPT=39443 DPT=53 LEN=62
[702626.318263] DBG@OUTPUT: IN= OUT=bond1.300 SRC=10.116.250.252 DST=10.116.0.2 LEN=82 TOS=0x00 PREC=0x00 TTL=64 ID=30608 PROTO=UDP SPT=39443 DPT=53 LEN=62
[702626.318266] DBG@OUTPUT: IN= OUT=bond1.300 SRC=10.116.250.252 DST=10.116.0.2 LEN=82 TOS=0x00 PREC=0x00 TTL=64 ID=30608 PROTO=UDP SPT=39443 DPT=53 LEN=62
[702626.318270] DBG@OUTPUT: IN= OUT=bond1.300 SRC=10.116.250.252 DST=10.116.0.2 LEN=82 TOS=0x00 PREC=0x00 TTL=64 ID=30608 PROTO=UDP SPT=39443 DPT=53 LEN=62
[702626.318284] DBG@POSTROUTING: IN= OUT=docker0 SRC=10.116.250.252 DST=10.116.160.7 LEN=82 TOS=0x00 PREC=0x00 TTL=64 ID=30608 PROTO=UDP SPT=39443 DPT=53 LEN=62
所以，通过添加路线
ip route add 10.116.0.0/23 dev docker0
现在它工作正常！
答案 0 :(得分：5)
将来，iptables-save的结果更容易阅读（无论如何）。
我在这里看不到任何遗漏。
KUBE-SERVICES陷阱10.116.0.2端口53 / UDP并将其传递给KUBE-SVC-TCOU7JCQXEZGVUNU
KUBE-SVC-TCOU7JCQXEZGVUNU只有一个端点，因此会跳转到KUBE-SEP-GSM3BZTEXEBWDXPN
KUBE-SEP-GSM3BZTEXEBWDXPN DNAT到10.116.160.7端口53 / UDP
如果断言10.116.160.7有效，而10.116.0.2没有，那确实很奇怪。它表明iptables规则根本没有触发。您是从节点本身还是从容器进行测试？
您使用什么网络？ L3（衬垫？）法兰绒？ OVS？还有别的吗？
云提供商（如果有）？
调试的第一步：运行：for c in PREROUTING OUTPUT; do iptables -t nat -I $c -d 10.116.0.2 -j LOG --log-prefix "DBG@$c: "; done
这会将iptables看到的任何数据包记录到您的服务IP。现在看dmesg。