在搭建openshift，需要用到域名解析，自搭dns服务器，以前都是用named的，这次接触到多两种方式

1.named

  2. [root@base ~]# yum install bind -y
  3. [root@base ~]# vim /etc/named.conf
  4. options {
  5.     listen-on port 53 { 10.83.15.30; };    # 这里是把本机作dns服务器
  6.     listen-on-v6 port 53 { ::1; };
  7.     directory     "/var/named";
  8.     dump-file     "/var/named/data/cache_dump.db";
  9.     statistics-file "/var/named/data/named_stats.txt";
  10.     memstatistics-file "/var/named/data/named_mem_stats.txt";
  11.     recursing-file  "/var/named/data/named.recursing";
  12.     secroots-file   "/var/named/data/named.secroots";
  13.     allow-query     { any; };
  14.   forwarders      { 10.83.15.254; };
  16.   recursion yes;
  18.     dnssec-enable no;
  19.     dnssec-validation no;
  21. [root@base ~]# named-checkconf         # 检查配置是否有问题
  22. [root@base ~]# vim /etc/named.rfc1912.zones      # 结尾加一个zone
  23. zone "ocp.example.com" IN {
  24.         type master;
  25.         file "ocp.example.com.zone";
  26.         allow-update { 10.83.15.30; };
  27. };
  29. [root@base ~]# named-checkconf
  31. [root@base ~]# vim /var/named/ocp.example.com.zone  # 新建zone
  32. $ORIGIN ocp.example.com.
  33. $TTL 600    ; 10 minutes
  34. @       IN SOA  dns.ocp.example.com. dnsadmin.ocp.example.com. (
  35.                 2021092901 ; serial
  36.                 10800      ; refresh (3 hours)
  37.                 900        ; retry (15 minutes)
  38.                 604800     ; expire (1 week)
  39.                 86400      ; minimum (1 day)
  40.                 )
  41.             NS   dns.ocp.example.com.
  42. $TTL 60 ; 1 minute
  44. dns              A    10.83.15.30
  45. api              A    10.83.15.30
  46. api-int          A    10.83.15.30
  47. bootstrap        A    10.83.15.30
  48. master1          A    10.83.15.30
  49. master2          A    10.83.15.30
  50. master3          A    10.83.15.30
  51. worker1          A    10.83.15.30
  52. worker2          A    10.83.15.30
  53. etcd-0          A    10.83.15.30
  54. etcd-1          A    10.83.15.30
  55. etcd-2          A    10.83.15.30
  57. [root@base ~]# named-checkconf
  58. [root@base ~]# systemctl start named
  59. [root@base ~]# systemctl enable named
  60. [root@base ~]# netstat -lntup | grep 53

2.etcd + coredns

  1. [root@base ~]# yum install -y etcd
  2. [root@base ~]# systemctl enable etcd --now
  4. [root@base ~]# wget https://github.com/coredns/coredns/releases/download/v1.6.9/coredns_1.6.9_linux_amd64.tgz
  5. [root@base ~]# tar zxvf coredns_1.6.9_linux_amd64.tgz
  6. [root@base ~]# mv coredns /usr/local/bin
  8. # 创建启动文件
  9. [root@base ~]# cat > /etc/systemd/system/coredns.service <<EOF
  10. [Unit]
  11. Description=CoreDNS DNS server
  12. Documentation=https://coredns.io
  13. After=network.target
  15. [Service]
  16. PermissionsStartOnly=true
  17. LimitNOFILE=1048576
  18. LimitNPROC=512
  19. CapabilityBoundingSet=CAP_NET_BIND_SERVICE
  20. AmbientCapabilities=CAP_NET_BIND_SERVICE
  21. NoNewPrivileges=true
  22. User=coredns
  23. WorkingDirectory=~
  24. ExecStart=/usr/local/bin/coredns -conf=/etc/coredns/Corefile
  25. ExecReload=/bin/kill -SIGUSR1 $MAINPID
  26. Restart=on-failure
  28. [Install]
  29. WantedBy=multi-user.target
  30. EOF
  32. # 创建Corefile配置文件，要大写
  33. [root@base ~]# cat /etc/coredns/Corefile
  34. .:53 { 
  35.     template IN A apps.ocp.example.com {
  36.     match .*apps.ocp.example.com 
  37.     answer "{{ .Name }} 60 IN A 10.83.15.30"
  38.     fallthrough
  39.     }
  40.     etcd {
  41.         path /skydns 
  42.         endpoint http://localhost:2379 
  43.         fallthrough 
  44.     }
  45.     cache 160
  46.     loadbalance 
  47.     log 
  48. }
  51. # 配置解析信息到etcd的skydns目录
  52. alias etcdctlv3='ETCDCTL_API=3 etcdctl'
  53. etcdctlv3 put /skydns/com/example/ocp/api '{"host":"10.83.15.30","ttl":60}'
  54. etcdctlv3 put /skydns/com/example/ocp/api-int '{"host":"10.83.15.30","ttl":60}'
  56. etcdctlv3 put /skydns/com/example/ocp/etcd-0 '{"host":"10.83.15.32","ttl":60}'
  57. etcdctlv3 put /skydns/com/example/ocp/etcd-1 '{"host":"10.83.15.33","ttl":60}'
  58. etcdctlv3 put /skydns/com/example/ocp/etcd-2 '{"host":"10.83.15.34","ttl":60}'
  60. etcdctlv3 put /skydns/com/example/ocp/_tcp/_etcd-server-ssl/x1 '{"host":"etcd-0.ocp.example.com","ttl":60,"priority":0,"weight":10,"port":2380}'
  61. etcdctlv3 put /skydns/com/example/ocp/_tcp/_etcd-server-ssl/x2 '{"host":"etcd-1.ocp.example.com","ttl":60,"priority":0,"weight":10,"port":2380}'
  62. etcdctlv3 put /skydns/com/example/ocp/_tcp/_etcd-server-ssl/x3 '{"host":"etcd-2.ocp.example.com","ttl":60,"priority":0,"weight":10,"port":2380}'
  64. # 除此之外再添加各节点主机名记录
  65. etcdctlv3 put /skydns/com/example/ocp/bootstrap '{"host":"10.83.15.31","ttl":60}'
  66. etcdctlv3 put /skydns/com/example/ocp/master1 '{"host":"10.83.15.32","ttl":60}'
  67. etcdctlv3 put /skydns/com/example/ocp/master2 '{"host":"10.83.15.33","ttl":60}'
  68. etcdctlv3 put /skydns/com/example/ocp/master3 '{"host":"10.83.15.34","ttl":60}'
  69. etcdctlv3 put /skydns/com/example/ocp/worker1 '{"host":"10.83.15.35","ttl":60}'
  70. etcdctlv3 put /skydns/com/example/ocp/worker2 '{"host":"10.83.15.36","ttl":60}'
  71. etcdctlv3 put /skydns/com/example/ocp/registry '{"host":"10.83.15.30","ttl":60}'
  73. [root@base ~]# systemctl start etcd
  74. [root@base ~]# systemctl start coredns 
  75. [root@base ~]# systemctl enable coredns --now
  76. [root@base ~]# systemctl enable etcd --now

3.dnsmasq

这是docker安装的

  1. docker search dnsmasq
  2. docker pull jpillora/dnsmasq
  4. docker exec -it xxxx  /bin/sh
  5. / # cat etc/dnsmasq.conf 
  6. cache-size=10000
  7. dns-forward-max=10000000
  8. address=/api.ocp.example.com/10.83.15.30
  9. address=/api-int.ocp.example.com/10.83.15.30
  10. address=/\*.apps.ocp.example.com/10.83.15.30
  11. address=/oauth-openshift.apps.ocp.example.com/10.83.15.30
  12. address=/bootstrap.ocp.example.com/10.83.15.31
  13. address=/console-openshift-console.apps.ocp.example.com/10.83.15.30
  14. address=/master1.ocp.example.com/10.83.15.32
  15. address=/master2.ocp.example.com/10.83.15.33
  16. address=/master3.ocp.example.com/10.83.15.34
  17. address=/worker1.ocp.example.com/10.83.15.35
  18. address=/worker2.ocp.example.com/10.83.15.36
  19. address=/etcd-0.ocp.example.com/10.83.15.32
  20. address=/etcd-1.ocp.example.com/10.83.15.33
  21. address=/etcd-2.ocp.example.com/10.83.15.34
  22. srv-host=_etcd-server-ssl._tcp.ocp.example.com,etcd-0.ocp.example.com,2380,0,100
  23. srv-host=_etcd-server-ssl._tcp.ocp.example.com,etcd-1.ocp.example.com,2380,0,100
  24. srv-host=_etcd-server-ssl._tcp.ocp.example.com,etcd-2.ocp.example.com,2380,0,100

验证

  1. 修改本机第一DNS为本机地址
  2. [root@base ~]# cat /etc/resolv.conf 
  3. nameserver 10.83.15.30
  4. nameserver 114.114.114.114
  6. [root@base coredns]# dig +short api.ocp.example.com @127.0.0.1
  7. 10.83.15.30
  8. [root@base coredns]# dig +short api-int.ocp.example.com @127.0.0.1
  9. 10.83.15.30
  10. [root@base coredns]# dig +short bootstrap.ocp.example.com @127.0.0.1
  11. 10.83.15.31
  12. [root@base coredns]# dig +short master1.ocp.example.com @127.0.0.1
  13. 10.83.15.32
  14. [root@base coredns]# dig +short master2.ocp.example.com @127.0.0.1
  15. 10.83.15.33
  16. [root@base coredns]# dig +short master3.ocp.example.com @127.0.0.1
  17. 10.83.15.34
  18. [root@base coredns]# dig +short worker1.ocp.example.com @127.0.0.1
  19. 10.83.15.35
  20. [root@base coredns]# dig +short worker2.ocp.example.com @127.0.0.1
  21. 10.83.15.36
  22. [root@base coredns]# dig +short -t SRV _etcd-server-ssl._tcp.ocp.example.com @127.0.0.1
  23. 10 33 2380 etcd-0.ocp.example.com.
  24. 10 33 2380 etcd-1.ocp.example.com.
  25. 10 33 2380 etcd-2.ocp.example.com.