Facts 變數查詢

ansible 使用 setup 模組可以列出 ansible_facts 變數，增加 filter=.. 參數可以過濾變數。

[deyu1@kvm19 ansible]$ ansible dev -m setup -a "filter=ansible_hostname"
kvm11 | SUCCESS => {
    "ansible_facts": {
        "ansible_hostname": "kvm11",
        "discovered_interpreter_python": "/usr/bin/python3"
    },
    "changed": false
}

如果不知變數完整名稱，可列出所有 ansible_facts 變數，使用管線處理過濾字串，例如：memory，得知總記憶體大小的變數為 ansible_memory_mb.real.total。

[deyu1@kvm19 ansible]$ ansible dev -m setup | grep memory -A16
        "ansible_memory_mb": {
            "nocache": {
                "free": 1555,
                "used": 216
            },
            "real": {
                "free": 1334,
                "total": 1771,
                "used": 437
            },
            "swap": {
                "cached": 0,
                "free": 95,
                "total": 95,
                "used": 0
            }
        },

總記憶體大小有另一變數 ansible_memtotal_mb。

[deyu1@kvm19 ansible]$ ansible dev -m setup -a "filter=ansible_memtotal_mb"
kvm11 | SUCCESS => {
    "ansible_facts": {
        "ansible_memtotal_mb": 1771,
        "discovered_interpreter_python": "/usr/bin/python3"
    },
    "changed": false
}

列出所有 ansible_facts 變數，使用管線處理過濾字串 bios，得知 bios 版本變數為 ansible_bios_version。

[deyu1@kvm19 ansible]$ ansible dev -m setup | grep bios
        "ansible_bios_date": "04/01/2014",
        "ansible_bios_vendor": "SeaBIOS",
        "ansible_bios_version": "1.16.0-4.el9",

如果變數內容太多，管線處理過濾字串不好判斷，可先將整個 ansible_facgts 變數存檔再查。
```
[deyu1@kvm19 ansible]$ ansible dev -m setup > setup.txt
```

例如 ansible_devices 變數有很多資料，vda 大小變數為 ansible_devices.vda.size。

[deyu1@kvm19 ansible]$ grep ansible_devices setup.txt -A218
        "ansible_devices": {
            "dm-0": {
                "holders": [],
                "host": "",
                "links": {
........................................................
            },
            "dm-1": {
                "holders": [],
                "host": "",
                "links": {
........................................................
            },
            "dm-2": {
                "holders": [],
                "host": "",
                "links": {
........................................................
                "sectors": "409600",
                "sectorsize": "512",
                "size": "200.00 MB",
                "support_discard": "512",
                "vendor": null,
                "virtual": 1
            },
            "vda": {
........................................................
                "partitions": {
                    "vda1": {
                        "holders": [],
                        "links": {
                            "ids": [],
                            "labels": [],
                            "masters": [],
                            "uuids": []
                        },
                        "sectors": "2048",
                        "sectorsize": 512,
                        "size": "1.00 MB",
                        "start": "2048",
                        "uuid": null
                    },
                    "vda2": {
........................................................
                        "sectors": "819200",
                        "sectorsize": 512,
                        "size": "400.00 MB",
                        "start": "4096",
                        "uuid": "51b32fc8-95cd-4f2e-b14b-209d8205871b"
                    },
                    "vda3": {
                        "holders": [
                            "vg_kvm11-swap",
                            "vg_kvm11-root"
                        ],
........................................................
                        "sectors": "7168000",
                        "sectorsize": 512,
                        "size": "3.42 GB",
                        "start": "823296",
                        "uuid": null
                    },
                    "vda4": {
........................................................
                        "sectors": "2",
                        "sectorsize": 512,
                        "size": "1.00 KB",
                        "start": "7991296",
                        "uuid": null
                    },
                    "vda5": {
                        "holders": [
                            "fieldwork-test"
                        ],
........................................................
                        "sectors": "614400",
                        "sectorsize": 512,
                        "size": "300.00 MB",
                        "start": "7995392",
                        "uuid": null
                    }
                },
                "removable": "0",
                "rotational": "1",
                "sas_address": null,
                "sas_device_handle": null,
                "scheduler_mode": "mq-deadline",
                "sectors": "12582912",
                "sectorsize": "512",
                "size": "6.00 GB",
                "support_discard": "512",
                "vendor": "0x1af4",
                "virtual": 1
            },
            "vdb": {
........................................................
                "holders": [],
                "partitions": {},
                "removable": "0",
                "rotational": "1",
                "sas_address": null,
                "sas_device_handle": null,
                "scheduler_mode": "mq-deadline",
                "sectors": "3145728",
                "sectorsize": "512",
                "size": "1.50 GB",
                "support_discard": "512",
                "vendor": "0x1af4",
                "virtual": 1
            }
        },