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bsr이 자동으로 해결할 수없는 스플릿 브레인 상황을 감지했습니다. 수동 복구가 필요합니다. 이 핸들러는 관리자의주의를 관리자의 주의를 환기시키는 데 사용될 수 있습니다.

net 섹션

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Define how to react if a split-brain scenario is detected and none of the two nodes is in primary role. (We detect split-brain scenarios when two nodes connect; split-brain decisions are always between two nodes.) The defined policies are:

  • disconnect No automatic resynchronization; simply disconnect.

  • discard-younger-primary

  • discard-older-primary Resynchronize from the node which became primary first ( discard-younger-primary) or last (discard-older-primary). If both nodes became primary independently, the discard-least-changes policy is used.

  • discard-zero-changes If only one of the nodes wrote data since the split brain situation was detected, resynchronize from this node to the other. If both nodes wrote data, disconnect.

  • discard-least-changes Resynchronize from the node with more modified blocks.

  • discard-node-nodename Always resynchronize to the named node.

after-sb-1pri policy

Define how to react if a split-brain scenario is detected, with one node in primary role and one node in secondary role. (We detect split-brain scenarios when two nodes connect, so split-brain decisions are always among two nodes.) The defined policies are:

  • disconnect No automatic resynchronization, simply disconnect.

  • consensus Discard the data on the secondary node if the after-sb-0pri algorithm would also discard the data on the secondary node. Otherwise, disconnect.

  • violently-as0p Always take the decision of the after-sb-0pri algorithm, even if it causes an erratic change of the primary's view of the data. This is only useful if a single-node file system (i.e., not OCFS2 or GFS) with the allow-two-primaries flag is used. This option can cause the primary node to crash, and should not be used.

  • discard-secondary Discard the data on the secondary node.

  • call-pri-lost-after-sb Always take the decision of the after-sb-0pri algorithm. If the decision is to discard the data on the primary node, call the pri-lost-after-sb handler on the primary node.

after-sb-2pri policy

Define how to react if a split-brain scenario is detected and both nodes are in primary role. (We detect split-brain scenarios when two nodes connect, so split-brain decisions are always among two nodes.) The defined policies are:

  • disconnect No automatic resynchronization, simply disconnect.

  • violently-as0p See the violently-as0p policy for after-sb-1pri.

  • call-pri-lost-after-sb Call the pri-lost-after-sb helper program on one of the machines unless that machine can demote to secondary. The helper program is expected to reboot the machine, which brings the node into a secondary role. Which machine runs the helper program is determined by the after-sb-0pri strategy.

allow-two-primaries

The most common way to configure DRBD devices is to allow only one node to be primary (and thus writable) at a time. In some scenarios it is preferable to allow two nodes to be primary at once; a mechanism outside of DRBD then must make sure that writes to the shared, replicated device happen in a coordinated way. This can be done with a shared-storage cluster file system like OCFS2 and GFS, or with virtual machine images and a virtual machine manager that can migrate virtual machines between physical machines. The allow-two-primaries parameter tells DRBD to allow two nodes to be primary at the same time. Never enable this option when using a non-distributed file system; otherwise, data corruption and node crashes will result!

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