Vertica节点宕机处理一例：
1. 查询数据库版本和各节点状态
```
dbadmin=> select version();
version
------------------------------------
Vertica Analytic Database v6.1.3-7
(1 row)
dbadmin=> select node_name, node_id, node_state, node_address from nodes;
node_name | node_id | node_state | node_address
--------------------+-------------------+------------+---------------
v_xxxxxxx_node0001 | 45035996273704980 | UP | 192.168.xx.xx
v_xxxxxxx_node0002 | 45035996273719008 | DOWN | 192.168.xx.xx
v_xxxxxxx_node0003 | 45035996273719012 | UP | 192.168.xx.xx
v_xxxxxxx_node0004 | 45035996273719016 | UP | 192.168.xx.xx
v_xxxxxxx_node0005 | 45035996273719020 | UP | 192.168.xx.xx
(5 rows)
<h1 id="2"> 2. 常规方式启动宕机节点失败</h1>
[常规方式启动宕机节点](http://www.cnblogs.com/jyzhao/p/3855601.html)失败，瞬间返回主界面，查询到报错如下：
*** Restarting hosts for database xxxxxxx ***
restart host 192.168.xx.xx with catalog v_xxxxxxx_node0002_catalog and data v_xxxxxxx_node0002_data
issuing multi-node restart
Spread does not seem to be running on 192.168.xx.xx. The database will not be started on this host.
The following host(s) are not available: 192.168.xx.xx.
You should get them running first. Operation can not be completed.
result of multi-node restart: K-safe parameters not met.
Restart Hosts result: K-safe parameters not met.
<h1 id="3"> 3. 进一步查看宕机节点的详细日志</h1>
发现/opt/vertica/log/adminTools-dbadmin.log中有这么一段错误日志：
Apr 16 10:55:23 Error code 1 []
Apr 16 10:56:19 dbadmin@192.168.xx.xx: /opt/vertica/bin/vertica --status -D /Vertica/xxxxxxx/v_xxxxxxx_node0001_catalog
Apr 16 10:56:19 Error code 1 ['vertica process is not running']
Apr 16 10:56:19 dbadmin@192.168.xx.xx: ps -aef | grep /opt/vertica/bin/vertica | grep "-D /Vertica/xxxxxxx/v_xxxxxxx_node0001_catalog" | grep -v "ps -aef"
<h1 id="4"> 4. 定位问题并解决 </h1>
基本确定是宕机节点的spread进程当前没有正常运行。
那么如何启动spread进程呢？
spread在Linux中是以服务的形式存在的。
/etc/init.d/spreadd status
/etc/init.d/spreadd start
/etc/init.d/spreadd stop
## 4.1 spread进程状态 ##
[root@Vertica02 log]# /etc/init.d/spreadd status
spread 已死，但 pid 文件仍存
Try using 'spreadd stop' to clear state
而正常节点的spread服务应该是正常运行的：
[root@Vertica01 ~]# /etc/init.d/spreadd status
spread (pid 19256) 正在运行...
## 4.2 尝试启动spread进程 ##
[root@Vertica02 log]# /etc/init.d/spreadd start
Starting spread daemon: [失败]
按提示尝试stop
[root@Vertica02 log]# /etc/init.d/spreadd stop
Stopping spread daemon: [失败]
[root@Vertica02 log]# /etc/init.d/spreadd help
用法：/etc/init.d/spreadd {start|stop|status|restart|condrestart}
[root@Vertica02 log]# /etc/init.d/spreadd restart
Stopping spread daemon: [失败]
Starting spread daemon: spread (pid 53230) 正在运行...
[确定]
[root@Vertica02 log]#
[root@Vertica02 log]# /etc/init.d/spreadd status
spread (pid 53230) 正在运行...
## 4.3 验证spread进程已经正常运行 ##
[root@Vertica02 log]# ps -ef|grep spread|grep -v grep
spread 53230 1 0 09:43 ? 00:00:00 /opt/vertica/spread/sbin/spread -n N192168062089 -c /opt/vertica/config/vspread.conf
spread进程起来后，然后就可以再次尝试[常规方式启动恢复宕机节点](http://www.cnblogs.com/jyzhao/p/3855601.html)了。
确定宕机节点已经在RECOVERING.
dbadmin=> select node_name, node_id, node_state, node_address from nodes;
node_name | node_id | node_state | node_address
--------------------+-------------------+------------+---------------
v_xxxxxxx_node0001 | 45035996273704980 | UP | 192.168.xx.xx
v_xxxxxxx_node0002 | 45035996273719008 | RECOVERING | 192.168.xx.xx
v_xxxxxxx_node0003 | 45035996273719012 | UP | 192.168.xx.xx
v_xxxxxxx_node0004 | 45035996273719016 | UP | 192.168.xx.xx
v_xxxxxxx_node0005 | 45035996273719020 | UP | 192.168.xx.xx
(5 rows)
当宕机节点的状态由RECOVERING->UP,即可确定恢复操作已完成。
## 4.4 尝试改用第二种恢复方案进行恢复 ##
很遗憾发现常规恢复的第一种方案无法成功（恢复整晚10小时+未成功）。
而估计的恢复时间，dstat监控宕机节点的网络接受流量速率以及数据目录的大小增加速率。
初步估计平均100M/s的速度copy恢复，1.3T数据量全部恢复大致也就需要4个小时。
故尝试变更为第二种方案进行恢复，即清空宕机节点所有文件完全恢复。之前的总结只说了思路，这里简单记录下这个恢复过程。
### 1.停掉RECOVERING的节点。 ###
常规停止不行就kill掉，均在admintools工具中可以操作。
dbadmin=> select node_name, node_id, node_state, node_address from nodes;
node_name | node_id | node_state | node_address
--------------------+-------------------+------------+---------------
v_xxxxxxx_node0001 | 45035996273704980 | UP | 192.168.xx.xx
v_xxxxxxx_node0002 | 45035996273719008 | DOWN | 192.168.xx.xx
v_xxxxxxx_node0003 | 45035996273719012 | UP | 192.168.xx.xx
v_xxxxxxx_node0004 | 45035996273719016 | UP | 192.168.xx.xx
v_xxxxxxx_node0005 | 45035996273719020 | UP | 192.168.xx.xx
(5 rows)
### 2.宕机节点原Vertica目录mv重命名xxxxxxx_old，然后后台删除这个目录（这步是为了尽快进入恢复阶段）。 ###
`nohup rm -rf /Vertica/xxxxxxx_old &`
### 3.重新建立目录（注意权限），拷贝vertica.conf到catalog目录中。 ###
`mkdir -p /Vertica/xxxxxxx/v_xxxxxxx_node0002_catalog && mkdir -p /Vertica/xxxxxxx/v_xxxxxxx_node0002_data`
### 4.节点1admintools工具启动宕机节点，进入恢复状态。 ###
*** Restarting hosts for database xxxxxxx ***
restart host 192.168.xx.xx with catalog v_xxxxxxx_node0002_catalog and data v_xxxxxxx_node0002_data
issuing multi-node restart
Node Status: v_xxxxxxx_node0002: (DOWN)
Node Status: v_xxxxxxx_node0002: (DOWN)
Node Status: v_xxxxxxx_node0002: (INITIALIZING)
Node Status: v_xxxxxxx_node0002: (RECOVERING)
Node Status: v_xxxxxxx_node0002: (RECOVERING)
Node Status: v_xxxxxxx_node0002: (RECOVERING)
Node Status: v_xxxxxxx_node0002: (RECOVERING)
Node Status: v_xxxxxxx_node0002: (RECOVERING)
Node Status: v_xxxxxxx_node0002: (RECOVERING)
Node Status: v_xxxxxxx_node0002: (RECOVERING)
Nodes UP: v_xxxxxxx_node0001, v_xxxxxxx_node0003, v_xxxxxxx_node0005, v_xxxxxxx_node0004
Nodes DOWN: v_xxxxxxx_node0002 (may be still initializing).
result of multi-node restart: 7
Restart Hosts result: 7
Vertica Analytic Database 6.1.3-7 Administration Tools
### 5.关注恢复状态。 ###
dbadmin=> select node_name, node_id, node_state, node_address from nodes;
node_name | node_id | node_state | node_address
--------------------+-------------------+------------+---------------
v_xxxxxxx_node0001 | 45035996273704980 | UP | 192.168.xx.xx
v_xxxxxxx_node0002 | 45035996273719008 | RECOVERING | 192.168.xx.xx
v_xxxxxxx_node0003 | 45035996273719012 | UP | 192.168.xx.xx
v_xxxxxxx_node0004 | 45035996273719016 | UP | 192.168.xx.xx
v_xxxxxxx_node0005 | 45035996273719020 | UP | 192.168.xx.xx
(5 rows)
同样，当宕机节点的状态由RECOVERING->UP,即可确定恢复操作已完成。
又遇到小插曲，总共单节点1.3T的数据恢复到1.2T的时候，不动了。
$ df -h /Vertica/
文件系统 容量 已用 可用 已用%% 挂载点
/dev/mapper/vg_vertica02-LogVol00
3.6T 1.2T 2.3T 34% /Vertica
此时dstat的监控信息看到，网络拷贝的流量同时几乎没有了。
恢复过程中发现有入库程序在跑,停掉入库程序重新恢复。
另外考虑到数据量，恢复前先删除了部分大表的历史分区，以缩短时间，最终恢复成功。
dbadmin=> select node_name, node_id, node_state, node_address from nodes;
node_name | node_id | node_state | node_address
--------------------+-------------------+------------+---------------
v_xxxxxxx_node0001 | 45035996273704980 | UP | 192.168.xx.xx
v_xxxxxxx_node0002 | 45035996273719008 | UP | 192.168.xx.xx
v_xxxxxxx_node0003 | 45035996273719012 | UP | 192.168.xx.xx
v_xxxxxxx_node0004 | 45035996273719016 | UP | 192.168.xx.xx
v_xxxxxxx_node0005 | 45035996273719020 | UP | 192.168.xx.xx
(5 rows)