Once we have installed ansible, it can be tested with localhost without much of additional configuration.
Lets setup a passwords login for user cipher on localhost which i will be using to test.
$ssh-copy-id cipher@localhost /usr/bin/ssh-copy-id: INFO: Source of key(s) to be installed: "/home/cipher/.ssh/id_rsa.pub" /usr/bin/ssh-copy-id: INFO: attempting to log in with the new key(s), to filter out any that are already installed /usr/bin/ssh-copy-id: INFO: 1 key(s) remain to be installed -- if you are prompted now it is to install the new keys cipher@localhost's password: Number of key(s) added: 1 Now try logging into the machine, with: "ssh 'cipher@localhost'" and check to make sure that only the key(s) you wanted were added.
Now user cipher can access cipher@localhost without any password, lets fire up a simple ansible command to test.
$ansible all -i localhost, -m ping
localhost | SUCCESS => {
"changed": false,
"ping": "pong"
}
results says we are able to connect to the server over ssh.
The above example was to test on a localhost without much configuration, when we want to manage large number of hosts they can be added in ansible inventory file located at /etc/ansible/hosts
here is a default ansible configuration file on fedora 26.
$cat /etc/ansible/hosts # This is the default ansible 'hosts' file. # # It should live in /etc/ansible/hosts # # - Comments begin with the '#' character # - Blank lines are ignored # - Groups of hosts are delimited by [header] elements # - You can enter hostnames or ip addresses # - A hostname/ip can be a member of multiple groups # Ex 1: Ungrouped hosts, specify before any group headers. ## green.example.com ## blue.example.com ## 192.168.100.1 ## 192.168.100.10 # Ex 2: A collection of hosts belonging to the 'webservers' group ## [webservers] ## alpha.example.org ## beta.example.org ## 192.168.1.100 ## 192.168.1.110 # If you have multiple hosts following a pattern you can specify # them like this: ## www[001:006].example.com # Ex 3: A collection of database servers in the 'dbservers' group ## [dbservers] ## ## db01.intranet.mydomain.net ## db02.intranet.mydomain.net ## 10.25.1.56 ## 10.25.1.57 # Here's another example of host ranges, this time there are no # leading 0s: ## db-[99:101]-node.example.com
Inventory file can be in INI deafult ansible syntax or it can be in json format.
mail.example.com
[webservers]
one.ansible.box
two.ansible.box
[dbservers]
three.ansible.box
four.ansible.box
Lets spin up 2 vms called linux3 and linux4 that can be used with ansible.
$sudo virsh vol-create-as store linux3 25G Vol linux3 created $ sudo virsh vol-create-as store linux4 25G Vol linux4 created
Centos 7 can be installed to these new volumes with virt-install command.
Setting up new vms is a time consuming process we can use virt-clone to clone the existing vm then sysprepping it to remove old configuration settings.
$virt-clone --force -o linux3 -n linux4 -f /dev/store/linux4 WARNING This will overwrite the existing path '/dev/store/linux4' WARNING The filesystem will not have enough free space to fully allocate the sparse file when the guest is running. 25600 M requested > 1955 M available Cloning linux3 | 25 GB 00:13:44 Clone 'linux4' created successfully.
resetting the newly created vm.
$virt-sysprep -d linux4 [ 0.0] Examining the guest ... [ 36.6] Performing "abrt-data" ... [ 36.6] Performing "backup-files" ... [ 43.8] Performing "bash-history" ... [ 43.8] Performing "blkid-tab" ... [ 43.8] Performing "crash-data" ... [ 43.8] Performing "cron-spool" ... [ 43.9] Performing "dhcp-client-state" ... [ 43.9] Performing "dhcp-server-state" ... [ 43.9] Performing "dovecot-data" ... [ 43.9] Performing "logfiles" ... [ 44.5] Performing "machine-id" ... [ 44.5] Performing "mail-spool" ... [ 44.5] Performing "net-hostname" ... [ 44.5] Performing "net-hwaddr" ... [ 44.5] Performing "pacct-log" ... [ 44.5] Performing "package-manager-cache" ... [ 44.6] Performing "pam-data" ... [ 44.6] Performing "passwd-backups" ... [ 44.6] Performing "puppet-data-log" ... [ 44.6] Performing "rh-subscription-manager" ... [ 44.6] Performing "rhn-systemid" ... [ 44.6] Performing "rpm-db" ... [ 44.6] Performing "samba-db-log" ... [ 44.6] Performing "script" ... [ 44.6] Performing "smolt-uuid" ... [ 44.6] Performing "ssh-hostkeys" ... [ 44.6] Performing "ssh-userdir" ... [ 44.6] Performing "sssd-db-log" ... [ 44.6] Performing "tmp-files" ... [ 44.7] Performing "udev-persistent-net" ... [ 44.7] Performing "utmp" ... [ 44.7] Performing "yum-uuid" ... [ 44.7] Performing "customize" ... [ 44.7] Setting a random seed [ 44.7] Setting the machine ID in /etc/machine-id [ 45.7] Performing "lvm-uuids" ...
Checking for the new vms created.
$ virsh list Id Name State ---------------------------------------------------- 2 linux3 running 4 linux4 running