This week on the podcast, Dwayne chats with Marc Trouard-Riolle, about Nutanix Cloud Clusters (NC2) on Azure and how to get started. Nutanix Cloud Clusters (NC2) on Microsoft Azure enables your applications to be run where you want them, on-premises or in the public cloud, all operated as a single cloud.<\/p>

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问题

HA恢复1个节点后

n
徽章

你好团队，

我正在运行一个3个小节点群集，在AHV升级到最新版本中，该服务器未能重新启动，因此AOS开始重建尝试恢复HA。经过几个小时的重建失败，看着日志，我看到了消息：“没有足够的空间”。

如果我没记错的3节点群集只能忍受一个节点，但是可以说两个运行的节点有足够的空间，是否可以还原HA？这基本上意味着经过一段时间的重建，如果剩下的两个节点之一失败，则群集仍在单个节点模式下。

只是好奇，因为看起来AOS试图重建HA奉献只有2个节点

    Hello Team,<\/p>

    \u00a0<\/p>

    I\u2019m running a small 3 node cluster, during an AHV upgrade to the latest version one of the servers\u00a0failed to reboot so AOS started to rebuild trying to restore HA. After several hours rebuilding failed, looking at the logs I saw the message:\u00a0\u201cnot enough space available\u201d.\u00a0<\/p>

    If I\u2019m not mistaken a 3\u00a0node cluster can tolerate only one node down, but lets say the two running\u00a0nodes had enough space, is it possible to restore HA? It basically means that after some time rebuilding, if one of the 2 remaining nodes fails, cluster is still\u00a0up in a single node\u00a0mode.<\/p>

    Just curious because it looked like AOS tried to rebuild HA despide only 2 nodes were up<\/p>","quoteUsername":"newlinksolutions","translations":{"Common":{"like":"Like","unlike":"Unlike"},"Forum":{"Quote":"Quote","Share":"Share"}}}">

    该主题已关闭以供评论

    3个答复

    谢尔盖·伊万诺夫（Sergei Ivanov）
    秩
    UserLevel 4
    徽章 +5

    一个3节点簇只能忍受1个节点故障。如果发生节点故障，数据重建过程将启动以防止数据丢失，并且群集中有足够的存储空间，即使另一个节点失败，所有数据也将是安全的。但是，如果2个节点下降，群集将无法运行，因为某些服务（例如Cassandra，Zookeeper等）将无法在一个节点上运行，并且它们只能忍受1个节点故障。

    员工SRE |Nutanix全球支持|NSS＃464，NCAP，VCP6.5-DCV，RHCE，CCNA，EMCSA，2XAWS和Google Cloud认证
    A 3 node cluster can tolerate only 1 node failure. In the event of a node failure, the data rebuild process kicks in to be able to prevent the data loss and if there is enough storage space in the cluster all the data will be safe even if another node fails. However, the cluster will not be able to run if 2 nodes go down, because some services (such as Cassandra, Zookeeper, etc) will not be able to run on a single node and they can tolerate only 1 node failure.<\/p>

    \u00a0<\/p>","quoteUsername":"Sergei Ivanov","translations":{"Common":{"like":"Like","unlike":"Unlike"},"Forum":{"Quote":"Quote","Share":"Share"}}}">

    n
    徽章

    你好谢尔盖，

    因此，如果没有足够的自由空间数据丢失是可能的，并且只有两个健康节点的HA也无法正常工作（而在Robo设置中，似乎群集可以与一个节点保持联系）。

    好吧，我不记得卡桑德拉是否有“没有足够可用的空间”，但这很奇怪，因为90％的空间是免费的（在AOS 5.18.1中，您不应该通过的极限是非常清楚地显示的）

    Hello Sergei,<\/p>

    \u00a0<\/p>

    So if there is not enough free space data loss is possible and HA with only two healthy nodes does not work as well (while in RoBo setup it seems that cluster can stay up with one node).<\/p>

    \u00a0<\/p>

    Well, I can\u2019t remember if the\u00a0\u201cnot enough space available\u201d came from Cassandra but it was quite weird because 90% of the space is free\u00a0(in AOS 5.18.1 the limit you should not pass is very clearly shown)<\/p>","quoteUsername":"newlinksolutions","translations":{"Common":{"like":"Like","unlike":"Unlike"},"Forum":{"Quote":"Quote","Share":"Share"}}}">

    谢尔盖·伊万诺夫（Sergei Ivanov）
    秩
    UserLevel 4
    徽章 +5

    在机器人群中，有一个差异使它们在1个节点下降时使它们活着，而这种差异是证人。在3个节点群集中，您没有证人，因此，如果第二个节点死亡，则该群集将完全下降，无论是否有足够的存储空间。

    员工SRE |Nutanix全球支持|NSS＃464，NCAP，VCP6.5-DCV，RHCE，CCNA，EMCSA，2XAWS和Google Cloud认证
    In RoBo clusters there is a difference that keeps them alive when 1 node goes down and that difference is the witness. In 3 node cluster you don\u2019t have a witness, so the cluster will be completely down if a 2nd node is dead no matter if there is enough storage space or not.<\/p>","quoteUsername":"Sergei Ivanov","translations":{"Common":{"like":"Like","unlike":"Unlike"},"Forum":{"Quote":"Quote","Share":"Share"}}}">
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