wikiv3:apache-ah
Table of Contents
Cluster Apache Active/Passive
Cenário:
- node01 - 192.0.2.12/24
- node02 - 192.0.2.13/24
- ip virtual - 192.0.2.14/24
node01
127.0.0.1 localhost localhost.localdomain localhost4 localhost4.localdomain4
::1 localhost localhost.localdomain localhost6 localhost6.localdomain6
192.0.2.12 node01.exemplo.org node01
192.0.2.13 node02.exemplo.org node02
192.0.2.14 site.exemplo.org site
node02
127.0.0.1 localhost localhost.localdomain localhost4 localhost4.localdomain4
::1 localhost localhost.localdomain localhost6 localhost6.localdomain6
192.0.2.12 node01.exemplo.org node01
192.0.2.13 node02.exemplo.org node02
192.0.2.14 site.exemplo.org site
Instalando o apache
root@node01:~# yum install httpd -y root@node02:~# yum install httpd -y
Página de status do apache
root@node01:~# cat /etc/httpd/conf.d/status.conf Listen 127.0.0.1:80 <Location /server-status> SetHandler server-status Order Deny,Allow Deny from All Allow from 127.0.0.1 </Location>
root@node02:~# cat /etc/httpd/conf.d/status.conf Listen 127.0.0.1:80 <Location /server-status> SetHandler server-status Order Deny,Allow Deny from All Allow from 127.0.0.1 </Location>
Comentando o Listen na configuração do apache
root@node01:~# sed -i 's/Listen/#Listen/' /etc/httpd/conf/httpd.conf root@node02:~# sed -i 's/Listen/#Listen/' /etc/httpd/conf/httpd.conf
Iniciando o apache e testando
root@node01:~# systemctl start httpd.service root@node01:~# wget http://127.0.0.1/server-status --2016-02-19 12:24:13-- http://127.0.0.1/server-status Conectando-se a 127.0.0.1:80... conectado. A requisição HTTP foi enviada, aguardando resposta... 200 OK Tamanho: 2741 (2,7K) [text/html] Salvando em: “server-status” 100%[=============================================================>] 2.741 --.-K/s em 0s 2016-02-19 12:24:13 (170 MB/s) - “server-status” salvo [2741/2741]
root@node02:~# systemctl start httpd.service root@node02:~# wget http://127.0.0.1/server-status --2016-02-19 12:38:42-- http://127.0.0.1/server-status Conectando-se a 127.0.0.1:80... conectado. A requisição HTTP foi enviada, aguardando resposta... 200 OK Tamanho: 2751 (2,7K) [text/html] Salvando em: “server-status” 100%[=============================================================>] 2.751 --.-K/s em 0s 2016-02-19 12:38:42 (290 MB/s) - “server-status” salvo [2751/2751]
Página de teste
root@node01:~# cat /var/www/html/index.html <!DOCTYPE html> <html lang="pt-br"> <head> <meta charset="UTF-8"/> <title>Apache HA</title> </head> <body> <h1>node01</h1> </body> </html>
root@node02:~# cat /var/www/html/index.html <!DOCTYPE html> <html lang="pt-br"> <head> <meta charset="UTF-8"/> <title>Apache HA</title> </head> <body> <h1>node02</h1> </body> </html>
Configurando o Listen da configuração do Apache para “escutar” no ip virtual
root@node01:~# systemctl stop httpd root@node02:~# systemctl stop httpd
root@node01:~# echo "Listen 192.0.2.14:80" | tee --append /etc/httpd/conf/httpd.conf root@node02:~# echo "Listen 192.0.2.14:80" | tee --append /etc/httpd/conf/httpd.conf
Instalando o Pacemaker e o Corosync
root@node01:~# yum install pcs root@node02:~# yum install pcs
Atribuindo uma senha para o usuário hacluster
root@node01:~# getent passwd hacluster hacluster:x:189:189:cluster user:/home/hacluster:/sbin/nologin
root@node02:~# getent passwd hacluster hacluster:x:189:189:cluster user:/home/hacluster:/sbin/nologin
Usuário usado para gerenciar os nós do cluster
root@node01:~# passwd hacluster root@node02:~# passwd hacluster
Configurando o Pacemaker
Liberando as portas no firewall
root@node01:~# firewall-cmd --permanent --add-service=high-availability success root@node01:~# firewall-cmd --reload success
root@node02:~# firewall-cmd --permanent --add-service=high-availability success root@node02:~# firewall-cmd --reload success
Autenticação entre os nós
root@node01:~# systemctl start pcsd.service root@node02:~# systemctl start pcsd.service
root@node01:~# pcs cluster auth node01 node02
Username: hacluster
Password:
node02: Authorized
node01: Authorized
Executar apenas no nós que fará o gerenciamento do cluster
Criando o cluster e adicionando os nós
root@node01:~# pcs cluster setup --name cluster_web node01 node02 Shutting down pacemaker/corosync services... Redirecting to /bin/systemctl stop pacemaker.service Redirecting to /bin/systemctl stop corosync.service Killing any remaining services... Removing all cluster configuration files... node01: Succeeded node02: Succeeded Synchronizing pcsd certificates on nodes node01, node02... node02: Success node01: Success Restaring pcsd on the nodes in order to reload the certificates... node02: Success node01: Success
root@node01:~# cat /etc/corosync/corosync.conf totem { version: 2 secauth: off cluster_name: cluster_web transport: udpu } nodelist { node { ring0_addr: node01 nodeid: 1 } node { ring0_addr: node02 nodeid: 2 } } quorum { provider: corosync_votequorum two_node: 1 } logging { to_logfile: yes logfile: /var/log/cluster/corosync.log to_syslog: yes }
root@node02:~# cat /etc/corosync/corosync.conf totem { version: 2 secauth: off cluster_name: cluster_web transport: udpu } nodelist { node { ring0_addr: node01 nodeid: 1 } node { ring0_addr: node02 nodeid: 2 } } quorum { provider: corosync_votequorum two_node: 1 } logging { to_logfile: yes logfile: /var/log/cluster/corosync.log to_syslog: yes }
Iniciando o cluster
root@node01:~# pcs cluster start --all node01: Starting Cluster... node02: Starting Cluster...
Status do cluster
root@node01:~# pcs status cluster Cluster Status: Last updated: Fri Feb 19 13:25:39 2016 Last change: Fri Feb 19 13:23:30 2016 by hacluster via crmd on node02 Stack: corosync Current DC: node02 (version 1.1.13-10.el7-44eb2dd) - partition with quorum 2 nodes and 0 resources configured Online: [ node01 node02 ] PCSD Status: node01: Online node02: Online
root@node01:~# pcs status nodes
Pacemaker Nodes:
Online: node01 node02
Standby:
Offline:
Pacemaker Remote Nodes:
Online:
Standby:
Offline:
root@node01:~# corosync-cmapctl | grep members runtime.totem.pg.mrp.srp.members.1.config_version (u64) = 0 runtime.totem.pg.mrp.srp.members.1.ip (str) = r(0) ip(192.0.2.12) runtime.totem.pg.mrp.srp.members.1.join_count (u32) = 1 runtime.totem.pg.mrp.srp.members.1.status (str) = joined runtime.totem.pg.mrp.srp.members.2.config_version (u64) = 0 runtime.totem.pg.mrp.srp.members.2.ip (str) = r(0) ip(192.0.2.13) runtime.totem.pg.mrp.srp.members.2.join_count (u32) = 1 runtime.totem.pg.mrp.srp.members.2.status (str) = joined
root@node01:~# pcs status corosync Membership information ---------------------- Nodeid Votes Name 1 1 node01 (local) 2 1 node02
Configurando o cluster
Verificando se existe erros
root@node01:~# crm_verify -L -V error: unpack_resources: Resource start-up disabled since no STONITH resources have been defined error: unpack_resources: Either configure some or disable STONITH with the stonith-enabled option error: unpack_resources: NOTE: Clusters with shared data need STONITH to ensure data integrity Errors found during check: config not valid
Na mensagem acima encontramos um erro no STONITH, como estamos usando um cluster com apenas dois nós, vamos desativar o opção STONITH.
<filhe bash> root@node01:~# pcs property set stonith-enabled=false </file>
Vamos “falar” para o Pacemaker para ignorar o quorum também
root@node01:~# pcs property set no-quorum-policy=ignore
root@node01:~# pcs property Cluster Properties: cluster-infrastructure: corosync cluster-name: cluster_web dc-version: 1.1.13-10.el7-44eb2dd have-watchdog: false no-quorum-policy: ignore stonith-enabled: false
Adicionando recurso ao cluster
Virtual IP
root@node01:~# pcs resource create virtual_ip ocf:heartbeat:IPaddr2 ip=192.0.2.14 cidr_netmask=32 op monitor interval=30s
<File bash> root@node01:~# pcs status resources virtual_ip (ocf::heartbeat:IPaddr2): Started node01 </file>
root@node01:~# ping -c2 192.0.2.14 PING 192.0.2.14 (192.0.2.14) 56(84) bytes of data. 64 bytes from 192.0.2.14: icmp_seq=1 ttl=64 time=0.043 ms 64 bytes from 192.0.2.14: icmp_seq=2 ttl=64 time=0.048 ms --- 192.0.2.14 ping statistics --- 2 packets transmitted, 2 received, 0% packet loss, time 999ms rtt min/avg/max/mdev = 0.043/0.045/0.048/0.007 ms
Adicionando recurso para o servidor web
root@node01:~# pcs resource create webserver ocf:heartbeat:apache configfile=/etc/httpd/conf/httpd.conf statusurl="http://localhost/server-status" op monitor interval=1min
Garantindo que o ip virtual e o servidor web inicie na no mesmo nó
root@node01:~# pcs constraint colocation add webserver virtual_ip INFINITY
Fazendo com que o ip virtual inicie primeiro que o servidor web
root@node01:~# pcs constraint order virtual_ip then webserver Adding virtual_ip webserver (kind: Mandatory) (Options: first-action=start then-action=start)
Dando preferência há um nó - caso ele tenha mais recurso.
root@node01:~# pcs constraint location webserver prefers node01=50
root@node01:~# pcs constraint Location Constraints: Resource: webserver Enabled on: node01 (score:50) Ordering Constraints: start virtual_ip then start webserver (kind:Mandatory) Colocation Constraints: webserver with virtual_ip (score:INFINITY)
Restartando o cluster e checando o status
root@node01:~# pcs cluster stop --all node02: Stopping Cluster (pacemaker)... node01: Stopping Cluster (pacemaker)... node01: Stopping Cluster (corosync)... node02: Stopping Cluster (corosync)... root@node01:~# pcs cluster start --all node01: Starting Cluster... node02: Starting Cluster...
root@node01:~# pcs status Cluster name: cluster_web Last updated: Fri Feb 19 16:10:49 2016 Last change: Fri Feb 19 16:07:00 2016 by root via cibadmin on node01 Stack: corosync Current DC: node01 (version 1.1.13-10.el7-44eb2dd) - partition with quorum 2 nodes and 2 resources configured Online: [ node01 node02 ] Full list of resources: virtual_ip (ocf::heartbeat:IPaddr2): Started node01 webserver (ocf::heartbeat:apache): Started node01 PCSD Status: node01: Online node02: Online Daemon Status: corosync: active/disabled pacemaker: active/disabled pcsd: active/disabled
Testando a High Availability
root@node01:~# firewall-cmd --add-service=http
root@gateway:~# lynx 192.0.2.14 Apache HA node01 Comandos: Use as setas para mover,'?' ajuda, 'q' sair, '<-' voltar. Setas para cima/baixo move.A direita segue um link; A esquerda para voltar. H)Ajuda O)Opções P)Imprimir G)Segue M)Principal Q)Sair /=procura [delete]=Histórico
Parando o node01
root@node01:~# pcs cluster stop node01 node01: Stopping Cluster (pacemaker)... node01: Stopping Cluster (corosync)...
root@node02:~# pcs status Cluster name: cluster_web Last updated: Fri Feb 19 16:22:03 2016 Last change: Fri Feb 19 16:07:00 2016 by root via cibadmin on node01 Stack: corosync Current DC: node02 (version 1.1.13-10.el7-44eb2dd) - partition with quorum 2 nodes and 2 resources configured Online: [ node02 ] OFFLINE: [ node01 ] Full list of resources: virtual_ip (ocf::heartbeat:IPaddr2): Started node02 webserver (ocf::heartbeat:apache): Started node02 PCSD Status: node01: Online node02: Online Daemon Status: corosync: active/disabled pacemaker: active/disabled pcsd: active/disabled
root@node02:~# firewall-cmd --add-service=http
root@gateway:~# lynx 192.0.2.14 Apache HA node02 Comandos: Use as setas para mover,'?' ajuda, 'q' sair, '<-' voltar. Setas para cima/baixo move.A direita segue um link; A esquerda para voltar. H)Ajuda O)Opções P)Imprimir G)Segue M)Principal Q)Sair /=procura [delete]=Histórico
Colocando os serviços na inicialização do sistema
root@node01:~# systemctl enable pcsd Created symlink from /etc/systemd/system/multi-user.target.wants/pcsd.service to /usr/lib/systemd/system/pcsd.service. root@node01:~# systemctl enable corosync Created symlink from /etc/systemd/system/multi-user.target.wants/corosync.service to /usr/lib/systemd/system/corosync.service. root@node01:~# systemctl enable pacemaker Created symlink from /etc/systemd/system/multi-user.target.wants/pacemaker.service to /usr/lib/systemd/system/pacemaker.service.
root@node02:~# systemctl enable pcsd Created symlink from /etc/systemd/system/multi-user.target.wants/pcsd.service to /usr/lib/systemd/system/pcsd.service. root@node02:~# systemctl enable corosync Created symlink from /etc/systemd/system/multi-user.target.wants/corosync.service to /usr/lib/systemd/system/corosync.service. root@node02:~# systemctl enable pacemaker Created symlink from /etc/systemd/system/multi-user.target.wants/pacemaker.service to /usr/lib/systemd/system/pacemaker.service.
Referências:
wikiv3/apache-ah.txt · Last modified: by 127.0.0.1