HX 4.0(2a)前向DNS监控和警报

简介

从HyperFlex 4.0(2a)开始，有一项新的监视程序服务将监控ESXi和SCVM主机名的可分辨性。如果HX无法解析主机名或访问DNS服务器，则监视程序进程会使用show dns命令来发出警报/事件。本文档将介绍CSCvt13947的解决方法 — 在HX连接上，一个或多个DNS服务器未响应，以从运行状况监控中发出DNS警报。

先决条件

解决此问题的先决条件是Hyperflex数据平台4.0(2a)。

背景信息

使用此新框架时，esxi主机名和scvm主机名必须在DNS中，才能使此事件触发器。

{
      "message": "HX Controller VM {HOSTNAME} one or more configured DNS servers not responding",
      "type": "NODE",
      "name": "DnsServerOfflineEvent",
      "severity": "warning"
    },

DNS也有警报：

    {
      "name": "HXA-NOD-0009",
      "description": "Triggered when one or more configured DNS servers on controller VM cannot be reached.",
      "category": "warning",
      "message": "One or more DNS servers configured on HX controller VM {HOSTNAME} not responding",
      "triggeringEvents" : ["DnsServerOfflineEvent"],
      "resetEvents" : ["DnsServerOnlineEvent"]
    }

以下是您在HX Connect中看到的故障示例：

以下是相应的show dns输出：

root@SpringpathController3G4ZKOQ6SE:~# show dns
 +------------------------------------------+------------------+--------------+---------------------------+
| DNS Name                                  | Resolved Address |    status    |           error           |
+-------------------------------------------+------------------+--------------+---------------------------+
| HX01.rchs.local                           | None             | Not Resolved | No DNS servers configured |
| HX04.rchs.local                           | None             | Not Resolved | No DNS servers configured |
| HX03.rchs.local                           | None             | Not Resolved | No DNS servers configured |
| HX02.rchs.local                           | None             | Not Resolved | No DNS servers configured |
| SpringpathController3G4ZKOQ6SE.rchs.local | None             | Not Resolved | No DNS servers configured |
| SpringpathController5DCAL5X6C2.rchs.local | None             | Not Resolved | No DNS servers configured |
| SpringpathControllerWZ2X6H20SF.rchs.local | None             | Not Resolved | No DNS servers configured |
| SpringpathControllerGR57QZVDED.rchs.local | None             | Not Resolved | No DNS servers configured |
+-------------------------------------------+------------------+--------------+---------------------------+
 Name Servers: ['172.16.199.101'], Search Domains: - rchs.local

如您所见，每个服务器的状态都为Not Resolved（未解析），错误是No DNS服务器未配置。此输出中的DNS服务器是172.16.199.101。

如果执行nslookup，我们会看到主机名SpringpathController3G4ZKOQ6SE未解析。

root@SpringpathController5DCAL5X6C2:~# nslookup SpringpathController3G4ZKOQ6SE
Server:         172.16.199.101
Address:        172.16.199.101#53

** server can't find SpringpathController3G4ZKOQ6SE: SERVFAIL

将show dns命令中的主机名添加到DNS后，show DNS将显示已解析的地址，状态将被解析：

root@SpringpathController3G4ZKOQ6SE:~# show dns
+-------------------------------------------+------------------+--------------+---------------------------+
| DNS Name                                  | Resolved Address |    status    |           error           |
+-------------------------------------------+------------------+--------------+---------------------------+
| HX01.rchs.local                           | 172.16.10.45     | Resolved     |  -                        |
| HX04.rchs.local                           | 172.16.10.48     | Resolved     |  -                        |
| HX03.rchs.local                           | 172.16.10.47     | Resolved     |  -                        |
| HX02.rchs.local                           | 172.16.10.46     | Resolved     |  -                        |
| SpringpathController3G4ZKOQ6SE.rchs.local | 172.16.10.41     | Resolved     |  -                        |
| SpringpathController5DCAL5X6C2.rchs.local | 172.16.10.44     | Resolved     |  -                        |
| SpringpathControllerWZ2X6H20SF.rchs.local | 172.16.10.43     | Resolved     |  -                        |
| SpringpathControllerGR57QZVDED.rchs.local | 172.16.10.42     | Resolved     |  -                        |
+-------------------------------------------+------------------+--------------+---------------------------+
 Name Servers: ['172.16.199.101'], Search Domains: - rchs.local

解决方法

解决方法是使用以下命令禁用监控功能。

root@hx-02-scvm-01:~# grep -i "monitor_dns_servers" /opt/springpath/hx-diag-tools/watchdog_config.json && sed -ie 's/"monitor_dns_servers": true/"monitor_dns_servers": false/' /opt/springpath/hx-diag-tools/watchdog_config.json && grep -i "monitor_dns_servers" /opt/springpath/hx-diag-tools/watchdog_config.json && restart watchdog
    "monitor_dns_servers": true,
    "monitor_dns_servers": false,
watchdog start/running, process 6350
root@hx-02-scvm-01:~#

此命令将/opt/springpath/hx-diag-tools/watchdog_config.json中的“monitor_dns_servers”设置为false并重新启动监视程序服务。

要恢复更改，请在每个存储控制器VM上运行以下命令：

root@hx-02-scvm-01:~# grep -i "monitor_dns_servers" /opt/springpath/hx-diag-tools/watchdog_config.json && sed -ie 's/"monitor_dns_servers": false/"monitor_dns_servers": true/' /opt/springpath/hx-diag-tools/watchdog_config.json && grep -i "monitor_dns_servers" /opt/springpath/hx-diag-tools/watchdog_config.json && restart watchdog
    "monitor_dns_servers": false,
    "monitor_dns_servers": true,
watchdog start/running, process 9473
root@hx-02-scvm-01:~#

在Hyperflex 4.0(2b)中，默认情况下禁用此功能。建议在进一步通知之前将其禁用。