如果他们通知你网页已经被删除，你可以通过使用Live HTTP Headers这个Firefox浏览器插件检查网页返回状态。

If they inform you that the page has been removed, you can confirm this by using an HTTP response testing tool like the Live HTTP Headers add-on for the Firefox browser.

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您可以利用此行为来判断用户没有在线，通过使用预定的代理来检查时间戳，并在出现更新的时间戳时重置用户状态。

You can use that behavior to tell that the user is not online by having a scheduled agent check the timestamp and reset the user's status when it turns old.

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可以通过使用lspv命令列出物理卷来检查卷组状态：这里显示了卷组名。

You can check the volume group status by listing physical volumes with LSPV. This shows the volume group name.

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