Ansible facts

facts组件是Ansible用于采集被管理机器设备信息的一个功能。可以使用setup模块查机器的所有facts信息，可以使用filter来查看指定信息。整个facts信息被包装在一个json格式的数据结构中，ansible_facts是最上层的值

[root@LVS_Master playbook]# ansible 192.168.170.129 -m setup
192.168.170.129 | SUCCESS => {
    "ansible_facts": {
        "ansible_all_ipv4_addresses": [
            "192.168.170.129", 
            "192.168.170.188"
        ], 
        "ansible_all_ipv6_addresses": [
            "fe80::20c:29ff:fea0:6cd4"
        ], 
        "ansible_architecture": "x86_64", 
        "ansible_bios_date": "07/02/2015", 
        "ansible_bios_version": "6.00", 
        "ansible_cmdline": {
            "KEYBOARDTYPE": "pc", 
            "KEYTABLE": "us", 
            "LANG": "zh_CN.UTF-8", 
            "quiet": true, 
            "rd_NO_DM": true, 
            "rd_NO_LUKS": true, 
            "rd_NO_LVM": true, 
            "rd_NO_MD": true, 
            "rhgb": true, 
            "ro": true, 
            "root": "UUID=b42623ce-7b8d-411c-bc1b-26ba53cfc4d8"
        }, 
        "ansible_date_time": {
            "date": "2016-11-22", 
            "day": "22", 
            "epoch": "1479793846", 
            "hour": "13", 
            "iso8601": "2016-11-22T05:50:46Z", 
            "iso8601_basic": "20161122T135046459819", 
            "iso8601_basic_short": "20161122T135046", 
            "iso8601_micro": "2016-11-22T05:50:46.460213Z", 
            "minute": "50", 
            "month": "11", 
            "second": "46", 
            "time": "13:50:46", 
            "tz": "CST", 
            "tz_offset": "+0800", 
            "weekday": "星期二", 
            "weekday_number": "2", 
            "weeknumber": "47", 
            "year": "2016"
        }, 
        "ansible_default_ipv4": {
            "address": "192.168.170.129", 
            "alias": "eth0", 
            "broadcast": "192.168.170.255", 
            "gateway": "192.168.170.2", 
            "interface": "eth0", 
            "macaddress": "00:0c:29:a0:6c:d4", 
            "mtu": 1500, 
            "netmask": "255.255.255.0", 
            "network": "192.168.170.0", 
            "type": "ether"
        }, 
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所有数据格式都是JSON格式，facts还支持查看指定信息，如下所示：

[root@LVS_Master playbook]# ansible 192.168.170.129 -m setup -a 'filter=ansible_all_ipv4_addresses'
192.168.170.129 | SUCCESS => {
    "ansible_facts": {
        "ansible_all_ipv4_addresses": [
            "192.168.170.129", 
            "192.168.170.188"
        ]
    }, 
    "changed": false
}