Expand|
测试的主题
|
将主站点故障转移到第三个站点。
辅助将重新注册到第三个站点。
|
|
测试先决条件
| -
DC1、DC2、DC3 上的 SAP HANA 正在运行。
-
集群已启动并运行，且没有错误或警告。
-
系统复制已就位并处于同步状态（检查
python systemReplicationStatus.py）。
|
|
测试步骤
|
将集群设置为 maintenance-mode 以便能够恢复。
使用 hdbnsutil -sr_takeover组成第三个节点
|
|
启动测试
|
执行 SAP HANA 命令on remotehost3: rh2adm>: hdbnsutil -sr_takeover
|
|
监控测试
|
在第三个站点 run: remotehost3:rh2adm> watch hdbnsutil -sr_state
|
|
预期结果
| -
第三个节点将成为主要节点。
-
辅助节点将主 master 更改为 remotehost3。以前的主节点需要重新注册到新主节点。
|
|
返回初始状态的方法
|
运行 Test 4：将主节点故障转移到第一个站点。
|
详细描述
例如，输出为：
mode: syncmem
primary masters: clusternode1
mode: syncmem
primary masters: clusternode1
Copy to Clipboard
Copied!
Toggle word wrap
Toggle overflow
在这种情况下，主数据库是 clusternode1。如果在 clusternode1 上运行这个命令，您将获得：
mode: primary
mode: primary
Copy to Clipboard
Copied!
Toggle word wrap
Toggle overflow
在这个主节点上，您还可以显示系统复制状态。它应该类似如下：
clusternode1:rh2adm> cdpy
clusternode1:rh2adm> python systemReplicationStatus.py
|Database |Host |Port |Service Name |Volume ID |Site ID |Site Name |Secondary |Secondary |Secondary |Secondary |Secondary |Replication |Replication |Replication |Secondary |
| | | | | | | |Host |Port |Site ID |Site Name |Active Status |Mode |Status |Status Details |Fully Synced |
|-------- |------ |----- |------------ |--------- |------- |--------- |--------- |--------- |--------- |--------- |------------- |----------- |----------- |-------------- |------------ |
|SYSTEMDB |clusternode1 |30201 |nameserver | 1 | 1 |DC1 |remotehost3 | 30201 | 3 |DC3 |YES |SYNCMEM |ACTIVE | | True |
|RH2 |clusternode1 |30207 |xsengine | 2 | 1 |DC1 |remotehost3 | 30207 | 3 |DC3 |YES |SYNCMEM |ACTIVE | | True |
|RH2 |clusternode1 |30203 |indexserver | 3 | 1 |DC1 |remotehost3 | 30203 | 3 |DC3 |YES |SYNCMEM |ACTIVE | | True |
|SYSTEMDB |clusternode1 |30201 |nameserver | 1 | 1 |DC1 |clusternode2 | 30201 | 2 |DC2 |YES |SYNCMEM |ACTIVE | | True |
|RH2 |clusternode1 |30207 |xsengine | 2 | 1 |DC1 |clusternode2 | 30207 | 2 |DC2 |YES |SYNCMEM |ACTIVE | | True |
|RH2 |clusternode1 |30203 |indexserver | 3 | 1 |DC1 |clusternode2 | 30203 | 2 |DC2 |YES |SYNCMEM |ACTIVE | | True |
status system replication site "3": ACTIVE
status system replication site "2": ACTIVE
overall system replication status: ACTIVE
Local System Replication State
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
mode: PRIMARY
site id: 1
site name: DC1
clusternode1:rh2adm> cdpy
clusternode1:rh2adm> python systemReplicationStatus.py
|Database |Host |Port |Service Name |Volume ID |Site ID |Site Name |Secondary |Secondary |Secondary |Secondary |Secondary |Replication |Replication |Replication |Secondary |
| | | | | | | |Host |Port |Site ID |Site Name |Active Status |Mode |Status |Status Details |Fully Synced |
|-------- |------ |----- |------------ |--------- |------- |--------- |--------- |--------- |--------- |--------- |------------- |----------- |----------- |-------------- |------------ |
|SYSTEMDB |clusternode1 |30201 |nameserver | 1 | 1 |DC1 |remotehost3 | 30201 | 3 |DC3 |YES |SYNCMEM |ACTIVE | | True |
|RH2 |clusternode1 |30207 |xsengine | 2 | 1 |DC1 |remotehost3 | 30207 | 3 |DC3 |YES |SYNCMEM |ACTIVE | | True |
|RH2 |clusternode1 |30203 |indexserver | 3 | 1 |DC1 |remotehost3 | 30203 | 3 |DC3 |YES |SYNCMEM |ACTIVE | | True |
|SYSTEMDB |clusternode1 |30201 |nameserver | 1 | 1 |DC1 |clusternode2 | 30201 | 2 |DC2 |YES |SYNCMEM |ACTIVE | | True |
|RH2 |clusternode1 |30207 |xsengine | 2 | 1 |DC1 |clusternode2 | 30207 | 2 |DC2 |YES |SYNCMEM |ACTIVE | | True |
|RH2 |clusternode1 |30203 |indexserver | 3 | 1 |DC1 |clusternode2 | 30203 | 2 |DC2 |YES |SYNCMEM |ACTIVE | | True |
status system replication site "3": ACTIVE
status system replication site "2": ACTIVE
overall system replication status: ACTIVE
Local System Replication State
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
mode: PRIMARY
site id: 1
site name: DC1
Copy to Clipboard
Copied!
Toggle word wrap
Toggle overflow
-
现在，我们有一个适当的环境，我们可以开始监控所有 3 个节点上的系统复制状态。
在测试启动前，应启动 3 个监视器。执行测试时，输出将改变。因此，只要测试还没有完成，使它们保持运行。
在旧的主节点上，clusternode1 在测试过程中在一个单独的窗口中运行：
clusternode1:rh2adm> watch -n 5 'python /usr/sap/$SAPSYSTEMNAME/HDB${TINSTANCE}/exe/python_support/systemReplicationStatus.py ; echo Status $?`
clusternode1:rh2adm> watch -n 5 'python /usr/sap/$SAPSYSTEMNAME/HDB${TINSTANCE}/exe/python_support/systemReplicationStatus.py ; echo Status $?`
Copy to Clipboard
Copied!
Toggle word wrap
Toggle overflow
clusternode1 上的输出将是：
Every 5.0s: python /usr/sap/$SAPSYSTEMNAME/HDB${TINSTANCE}/exe/python_support/systemReplicati... clusternode1: Tue XXX XX HH:MM:SS 2023
|Database |Host |Port |Service Name |Volume ID |Site ID |Site Name |Secondary |Secondary |Secondary |Secondary |Secondary |
Replication |Replication |Replication |Secondary |
| | | | | | | |Host |Port |Site ID |Site Name |Active Status |
Mode |Status |Status Details |Fully Synced |
|-------- |------ |----- |------------ |--------- |------- |--------- |--------- |--------- |--------- |--------- |------------- |
----------- |----------- |-------------- |------------ |
|SYSTEMDB |clusternode1 |30201 |nameserver | 1 | 1 |DC1 |remotehost3 | 30201 | 3 |DC3 |YES |
ASYNC |ACTIVE | | True |
|RH2 |clusternode1 |30207 |xsengine | 2 | 1 |DC1 |remotehost3 | 30207 | 3 |DC3 |YES |
ASYNC |ACTIVE | | True |
|RH2 |clusternode1 |30203 |indexserver | 3 | 1 |DC1 |remotehost3 | 30203 | 3 |DC3 |YES |
ASYNC |ACTIVE | | True |
|SYSTEMDB |clusternode1 |30201 |nameserver | 1 | 1 |DC1 |clusternode2 | 30201 | 2 |DC2 |YES |
SYNCMEM |ACTIVE | | True |
|RH2 |clusternode1 |30207 |xsengine | 2 | 1 |DC1 |clusternode2 | 30207 | 2 |DC2 |YES |
SYNCMEM |ACTIVE | | True |
|RH2 |clusternode1 |30203 |indexserver | 3 | 1 |DC1 |clusternode2 | 30203 | 2 |DC2 |YES |
SYNCMEM |ACTIVE | | True |
status system replication site "3": ACTIVE
status system replication site "2": ACTIVE
overall system replication status: ACTIVE
Local System Replication State
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
mode: PRIMARY
site id: 1
site name: DC1
Status 15
Every 5.0s: python /usr/sap/$SAPSYSTEMNAME/HDB${TINSTANCE}/exe/python_support/systemReplicati... clusternode1: Tue XXX XX HH:MM:SS 2023
|Database |Host |Port |Service Name |Volume ID |Site ID |Site Name |Secondary |Secondary |Secondary |Secondary |Secondary |
Replication |Replication |Replication |Secondary |
| | | | | | | |Host |Port |Site ID |Site Name |Active Status |
Mode |Status |Status Details |Fully Synced |
|-------- |------ |----- |------------ |--------- |------- |--------- |--------- |--------- |--------- |--------- |------------- |
----------- |----------- |-------------- |------------ |
|SYSTEMDB |clusternode1 |30201 |nameserver | 1 | 1 |DC1 |remotehost3 | 30201 | 3 |DC3 |YES |
ASYNC |ACTIVE | | True |
|RH2 |clusternode1 |30207 |xsengine | 2 | 1 |DC1 |remotehost3 | 30207 | 3 |DC3 |YES |
ASYNC |ACTIVE | | True |
|RH2 |clusternode1 |30203 |indexserver | 3 | 1 |DC1 |remotehost3 | 30203 | 3 |DC3 |YES |
ASYNC |ACTIVE | | True |
|SYSTEMDB |clusternode1 |30201 |nameserver | 1 | 1 |DC1 |clusternode2 | 30201 | 2 |DC2 |YES |
SYNCMEM |ACTIVE | | True |
|RH2 |clusternode1 |30207 |xsengine | 2 | 1 |DC1 |clusternode2 | 30207 | 2 |DC2 |YES |
SYNCMEM |ACTIVE | | True |
|RH2 |clusternode1 |30203 |indexserver | 3 | 1 |DC1 |clusternode2 | 30203 | 2 |DC2 |YES |
SYNCMEM |ACTIVE | | True |
status system replication site "3": ACTIVE
status system replication site "2": ACTIVE
overall system replication status: ACTIVE
Local System Replication State
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
mode: PRIMARY
site id: 1
site name: DC1
Status 15
Copy to Clipboard
Copied!
Toggle word wrap
Toggle overflow
在 remotehost3 上运行相同的命令：
remotehost3:rh2adm> watch -n 5 'python /usr/sap/$SAPSYSTEMNAME/HDB${TINSTANCE}/exe/python_support/systemReplicationStatus.py ; echo Status $?'
remotehost3:rh2adm> watch -n 5 'python /usr/sap/$SAPSYSTEMNAME/HDB${TINSTANCE}/exe/python_support/systemReplicationStatus.py ; echo Status $?'
Copy to Clipboard
Copied!
Toggle word wrap
Toggle overflow
响应将是：
this system is either not running or not primary system replication site
this system is either not running or not primary system replication site
Copy to Clipboard
Copied!
Toggle word wrap
Toggle overflow
测试启动故障转移后，输出将改变。在测试启动前，输出类似于主节点的示例。
在第二个节点上启动：
clusternode2:rh2adm> watch -n 10 'hdbnsutil -sr_state | grep masters'
clusternode2:rh2adm> watch -n 10 'hdbnsutil -sr_state | grep masters'
Copy to Clipboard
Copied!
Toggle word wrap
Toggle overflow
这将显示当前 master clusternode1，并在启动故障转移后立即切换。
-
为确保一切配置正确，还要检查
global.ini。
-
在 DC1、DC2 和 DC3 上检查
global.ini。
在所有三个节点上，global.ini 应该包含：
[persistent]
log_mode=normal
[system_replication]
register_secondaries_on_takeover=true
[persistent]
log_mode=normal
[system_replication]
register_secondaries_on_takeover=true
Copy to Clipboard
Copied!
Toggle word wrap
Toggle overflow
您可以使用以下内容编辑 global.ini：
clusternode1:rh2adm>vim /usr/sap/$SAPSYSTEMNAME/SYS/global/hdb/custom/config/global.ini
clusternode1:rh2adm>vim /usr/sap/$SAPSYSTEMNAME/SYS/global/hdb/custom/config/global.ini
Copy to Clipboard
Copied!
Toggle word wrap
Toggle overflow
[可选] 将集群置于 maintenance-mode ：
pcs property set maintenance-mode=true
[root@clusternode1]# pcs property set maintenance-mode=true
Copy to Clipboard
Copied!
Toggle word wrap
Toggle overflow
在测试过程中，您会发现故障转移将使用 和，而不设置 maintenance-mode。因此，您可以在不使用它的情况下运行第一个测试。在恢复它时，我只想向您显示，而是使用。这是主要方面的一个选项，不能访问。
开始测试：故障切换到 DC3。在 remotehost3 上，请运行：
remotehost3:rh2adm> hdbnsutil -sr_takeover
done.
remotehost3:rh2adm> hdbnsutil -sr_takeover
done.
Copy to Clipboard
Copied!
Toggle word wrap
Toggle overflow
测试已启动，现在请检查之前启动的 monitor 的输出。
在 clusternode1 上，系统复制状态将丢失与 remotehost3 和 clusternode2 (DC2)的关系：
Every 5.0s: python /usr/sap/RH2/HDB02/exe/python_support/systemReplicationStatus.py ; echo Status $? clusternode1: Mon Sep 4 11:52:16 2023
|Database |Host |Port |Service Name |Volume ID |Site ID |Site Name |Secondary |Secondary |Secondary |Secondary |Secondary |Replication |Replication |Replic
ation |Secondary |
| | | | | | | |Host |Port |Site ID |Site Name |Active Status |Mode |Status |Status
Details |Fully Synced |
|-------- |------ |----- |------------ |--------- |------- |--------- |--------- |--------- |--------- |--------- |------------- |----------- |----------- |------
---------------------- |------------ |
|SYSTEMDB |clusternode1 |30201 |nameserver | 1 | 1 |DC1 |clusternode2 | 30201 | 2 |DC2 |YES |SYNCMEM |ERROR |Commun
ication channel closed | False |
|RH2 |clusternode1 |30207 |xsengine | 2 | 1 |DC1 |clusternode2 | 30207 | 2 |DC2 |YES |SYNCMEM |ERROR |Commun
ication channel closed | False |
|RH2 |clusternode1 |30203 |indexserver | 3 | 1 |DC1 |clusternode2 | 30203 | 2 |DC2 |YES |SYNCMEM |ERROR |Commun
ication channel closed | False |
status system replication site "2": ERROR
overall system replication status: ERROR
Local System Replication State
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
mode: PRIMARY
site id: 1
site name: DC1
Status 11
Every 5.0s: python /usr/sap/RH2/HDB02/exe/python_support/systemReplicationStatus.py ; echo Status $? clusternode1: Mon Sep 4 11:52:16 2023
|Database |Host |Port |Service Name |Volume ID |Site ID |Site Name |Secondary |Secondary |Secondary |Secondary |Secondary |Replication |Replication |Replic
ation |Secondary |
| | | | | | | |Host |Port |Site ID |Site Name |Active Status |Mode |Status |Status
Details |Fully Synced |
|-------- |------ |----- |------------ |--------- |------- |--------- |--------- |--------- |--------- |--------- |------------- |----------- |----------- |------
---------------------- |------------ |
|SYSTEMDB |clusternode1 |30201 |nameserver | 1 | 1 |DC1 |clusternode2 | 30201 | 2 |DC2 |YES |SYNCMEM |ERROR |Commun
ication channel closed | False |
|RH2 |clusternode1 |30207 |xsengine | 2 | 1 |DC1 |clusternode2 | 30207 | 2 |DC2 |YES |SYNCMEM |ERROR |Commun
ication channel closed | False |
|RH2 |clusternode1 |30203 |indexserver | 3 | 1 |DC1 |clusternode2 | 30203 | 2 |DC2 |YES |SYNCMEM |ERROR |Commun
ication channel closed | False |
status system replication site "2": ERROR
overall system replication status: ERROR
Local System Replication State
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
mode: PRIMARY
site id: 1
site name: DC1
Status 11
Copy to Clipboard
Copied!
Toggle word wrap
Toggle overflow
集群仍然不会注意到此行为。如果您检查系统复制状态的返回码，则返回码 11 表示错误，这告诉您出现问题。如果您有访问权限，现在最好进入 maintenance-mode。
remotehost3 变为新的主主，而 clusternode2 (DC2)会在 remotehost3 上自动注册为新主。
remotehost3 的系统复制状态的输出示例：
Every 5.0s: python /usr/sap/RH2/HDB02/exe/python_support/systemReplicationStatus.py ; echo Status $? remotehost3: Mon Sep 4 13:55:29 2023
|Database |Host |Port |Service Name |Volume ID |Site ID |Site Name |Secondary |Secondary |Secondary |Secondary |Secondary |Replication |Replication |Replic
ation |Secondary |
| | | | | | | |Host |Port |Site ID |Site Name |Active Status |Mode |Status |Status
Details |Fully Synced |
|-------- |------ |----- |------------ |--------- |------- |--------- |--------- |--------- |--------- |--------- |------------- |----------- |----------- |------
-------- |------------ |
|SYSTEMDB |remotehost3 |30201 |nameserver | 1 | 3 |DC3 |clusternode2 | 30201 | 2 |DC2 |YES |SYNCMEM |ACTIVE |
| True |
|RH2 |remotehost3 |30207 |xsengine | 2 | 3 |DC3 |clusternode2 | 30207 | 2 |DC2 |YES |SYNCMEM |ACTIVE |
| True |
|RH2 |remotehost3 |30203 |indexserver | 3 | 3 |DC3 |clusternode2 | 30203 | 2 |DC2 |YES |SYNCMEM |ACTIVE |
| True |
status system replication site "2": ACTIVE
overall system replication status: ACTIVE
Local System Replication State
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
mode: PRIMARY
site id: 3
site name: DC3
Status 15
Every 5.0s: python /usr/sap/RH2/HDB02/exe/python_support/systemReplicationStatus.py ; echo Status $? remotehost3: Mon Sep 4 13:55:29 2023
|Database |Host |Port |Service Name |Volume ID |Site ID |Site Name |Secondary |Secondary |Secondary |Secondary |Secondary |Replication |Replication |Replic
ation |Secondary |
| | | | | | | |Host |Port |Site ID |Site Name |Active Status |Mode |Status |Status
Details |Fully Synced |
|-------- |------ |----- |------------ |--------- |------- |--------- |--------- |--------- |--------- |--------- |------------- |----------- |----------- |------
-------- |------------ |
|SYSTEMDB |remotehost3 |30201 |nameserver | 1 | 3 |DC3 |clusternode2 | 30201 | 2 |DC2 |YES |SYNCMEM |ACTIVE |
| True |
|RH2 |remotehost3 |30207 |xsengine | 2 | 3 |DC3 |clusternode2 | 30207 | 2 |DC2 |YES |SYNCMEM |ACTIVE |
| True |
|RH2 |remotehost3 |30203 |indexserver | 3 | 3 |DC3 |clusternode2 | 30203 | 2 |DC2 |YES |SYNCMEM |ACTIVE |
| True |
status system replication site "2": ACTIVE
overall system replication status: ACTIVE
Local System Replication State
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
mode: PRIMARY
site id: 3
site name: DC3
Status 15
Copy to Clipboard
Copied!
Toggle word wrap
Toggle overflow
returncode 15 还表示一切都是 okay，但缺少 clusternode1。这必须手动重新注册。前一个主 clusternode1 没有被列出，因此复制关系会丢失。
如果还没有在集群的一个节点上设置 maintenance-mode 之前完成，使用以下命令：
pcs property set maintenance-mode=true
[root@clusternode1]# pcs property set maintenance-mode=true
Copy to Clipboard
Copied!
Toggle word wrap
Toggle overflow
您可以运行以下命令来检查 maintenance-mode 是否活跃：
pcs resource
[root@clusternode1]# pcs resource
* Clone Set: SAPHanaTopology_RH2_02-clone [SAPHanaTopology_RH2_02] (unmanaged):
* SAPHanaTopology_RH2_02 (ocf::heartbeat:SAPHanaTopology): Started clusternode2 (unmanaged)
* SAPHanaTopology_RH2_02 (ocf::heartbeat:SAPHanaTopology): Started clusternode1 (unmanaged)
* Clone Set: SAPHana_RH2_02-clone [SAPHana_RH2_02] (promotable, unmanaged):
* SAPHana_RH2_02 (ocf::heartbeat:SAPHana): Slave clusternode2 (unmanaged)
* SAPHana_RH2_02 (ocf::heartbeat:SAPHana): Master clusternode1 (unmanaged)
* vip_RH2_02_MASTER (ocf::heartbeat:IPaddr2): Started clusternode1 (unmanaged)
Copy to Clipboard
Copied!
Toggle word wrap
Toggle overflow
资源显示非受管状态，这表示集群处于 maintenance-mode=true。虚拟 IP 地址仍然在 clusternode1 上启动。如果要在另一个节点上使用此 IP，请在设置 maintanence-mode=true 前禁用 vip_RH2_02_MASTER。
pcs resource disable vip_RH2_02_MASTER
[root@clusternode1]# pcs resource disable vip_RH2_02_MASTER
Copy to Clipboard
Copied!
Toggle word wrap
Toggle overflow
当我们检查 clusternode1 上的 sr_state 时，您将只看到一个与 DC2 的关系：
clusternode1:rh2adm> hdbnsutil -sr_state
System Replication State
~~~~~~~~~~~~~~~~~~~~~~~~
online: true
mode: primary
operation mode: primary
site id: 1
site name: DC1
is source system: true
is secondary/consumer system: false
has secondaries/consumers attached: true
is a takeover active: false
is primary suspended: false
Host Mappings:
~~~~~~~~~~~~~~
clusternode1 -> [DC2] clusternode2
clusternode1 -> [DC1] clusternode1
Site Mappings:
~~~~~~~~~~~~~~
DC1 (primary/primary)
|---DC2 (syncmem/logreplay)
Tier of DC1: 1
Tier of DC2: 2
Replication mode of DC1: primary
Replication mode of DC2: syncmem
Operation mode of DC1: primary
Operation mode of DC2: logreplay
Mapping: DC1 -> DC2
done.
clusternode1:rh2adm> hdbnsutil -sr_state
System Replication State
~~~~~~~~~~~~~~~~~~~~~~~~
online: true
mode: primary
operation mode: primary
site id: 1
site name: DC1
is source system: true
is secondary/consumer system: false
has secondaries/consumers attached: true
is a takeover active: false
is primary suspended: false
Host Mappings:
~~~~~~~~~~~~~~
clusternode1 -> [DC2] clusternode2
clusternode1 -> [DC1] clusternode1
Site Mappings:
~~~~~~~~~~~~~~
DC1 (primary/primary)
|---DC2 (syncmem/logreplay)
Tier of DC1: 1
Tier of DC2: 2
Replication mode of DC1: primary
Replication mode of DC2: syncmem
Operation mode of DC1: primary
Operation mode of DC2: logreplay
Mapping: DC1 -> DC2
done.
Copy to Clipboard
Copied!
Toggle word wrap
Toggle overflow
但是，当检查 DC2 时，主数据库服务器为 DC3。因此，DC1 的信息不正确。
clusternode2:rh2adm> hdbnsutil -sr_state
clusternode2:rh2adm> hdbnsutil -sr_state
Copy to Clipboard
Copied!
Toggle word wrap
Toggle overflow
如果我们在 DC1 上检查系统复制状态，则返回码为 12 （未知）。因此，需要重新注册 DC1。
您可以使用此命令将以前的主 clusternode1 注册为 remotehost3 的新辅助设备：
clusternode1:rh2adm> hdbnsutil -sr_register --remoteHost=remotehost3 --remoteInstance=${TINSTANCE} --replicationMode=async --name=DC1 --remoteName=DC3 --operationMode=logreplay --online
clusternode1:rh2adm> hdbnsutil -sr_register --remoteHost=remotehost3 --remoteInstance=${TINSTANCE} --replicationMode=async --name=DC1 --remoteName=DC3 --operationMode=logreplay --online
Copy to Clipboard
Copied!
Toggle word wrap
Toggle overflow
注册完成后，您将在 remotehost3 上看到复制三个站点，状态（重新代码）将变为 15。如果此操作失败，则必须手动删除 DC1 和 DC3 上的复制关系。请按照 Register Secondary 中描述的说明进行操作。例如，列出现有关系：
hdbnsutil -sr_state
hdbnsutil -sr_state
Copy to Clipboard
Copied!
Toggle word wrap
Toggle overflow
删除您可以使用的现有关系示例：
clusternode1:rh2adm> hdbnsutil -sr_unregister --name=DC2
clusternode1:rh2adm> hdbnsutil -sr_unregister --name=DC2
Copy to Clipboard
Copied!
Toggle word wrap
Toggle overflow
这通常不需要这样做。
我们假定测试 4 将在测试 3 后执行。因此，恢复步骤是运行测试 4。
红帽全球峰会
'%20d='M201.5%20305.5c-13.8%200-24.9-11.1-24.9-24.6%200-13.8%2011.1-24.9%2024.9-24.9%2013.6%200%2024.6%2011.1%2024.6%2024.9%200%2013.6-11.1%2024.6-24.6%2024.6zM504%20256c0%20137-111%20248-248%20248S8%20393%208%20256%20119%208%20256%208s248%20111%20248%20248zm-132.3-41.2c-9.4%200-17.7%203.9-23.8%2010-22.4-15.5-52.6-25.5-86.1-26.6l17.4-78.3%2055.4%2012.5c0%2013.6%2011.1%2024.6%2024.6%2024.6%2013.8%200%2024.9-11.3%2024.9-24.9s-11.1-24.9-24.9-24.9c-9.7%200-18%205.8-22.1%2013.8l-61.2-13.6c-3-.8-6.1%201.4-6.9%204.4l-19.1%2086.4c-33.2%201.4-63.1%2011.3-85.5%2026.8-6.1-6.4-14.7-10.2-24.1-10.2-34.9%200-46.3%2046.9-14.4%2062.8-1.1%205-1.7%2010.2-1.7%2015.5%200%2052.6%2059.2%2095.2%20132%2095.2%2073.1%200%20132.3-42.6%20132.3-95.2%200-5.3-.6-10.8-1.9-15.8%2031.3-16%2019.8-62.5-14.9-62.5zM302.8%20331c-18.2%2018.2-76.1%2017.9-93.6%200-2.2-2.2-6.1-2.2-8.3%200-2.5%202.5-2.5%206.4%200%208.6%2022.8%2022.8%2087.3%2022.8%20110.2%200%202.5-2.2%202.5-6.1%200-8.6-2.2-2.2-6.1-2.2-8.3%200zm7.7-75c-13.6%200-24.6%2011.1-24.6%2024.9%200%2013.6%2011.1%2024.6%2024.6%2024.6%2013.8%200%2024.9-11.1%2024.9-24.6%200-13.8-11-24.9-24.9-24.9z'/%3e%3c/svg%3e){kind=small}