无法resize实例

编辑计算节点和控制节点的/etc/nova/nova.conf文件，添加如下配置行

allow_migrate_to_same_host = True
scheduler_default_filters = AllHostsFilter
allow_resize_to_same_host = True

重启计算节点和控制节点服务

## 控制节点
sudo service nova-api restart
sudo service nova-consoleauth restart
sudo service nova-scheduler restart
sudo service nova-conductor restart
sudo service nova-novncproxy restart

## 计算节点
sudo service nova-compute restart

某个计算节点无法被有效利用，总是不分配实例

当每个计算节点总是不分配实例，资源一直被闲置时，需要检查/var/log/nova/nova-schedule.log，从日志中得出有价值的信息来。
一般来说，会有如下信息。

2017-07-20 16:50:31.994 2930 INFO nova.filters [req-263d3a98-3ec6-448a-89e9-72ce84bbc15a db88697b9df14f888f0aa48397c41536 e6aa14cf447b415f94c6c29d992e55a3 - - -] Filtering removed all hosts for the request with instance ID '28a73a5e-7563-41d5-9b0a-b9dee01147fe'. Filter results: ['RetryFilter: (start: 3, end: 3)', 'AvailabilityZoneFilter: (start: 3, end: 3)', 'RamFilter: (start: 3, end: 3)', 'DiskFilter: (start: 3, end: 0)']

此信息显示了为了创建当前实例进行的节点筛选过程，可以看到，满足条件的磁盘节点有0个，所以无法分配新的实例。
而各资源的使用情况，我们可以在nova_api数据库的inventories表中查询到。
注意：当新建新的同名的计算节点时，数据可能不会被更新，从而导致数据不一致的情况，数据库里的数据与实际数据不相符。从而无法有效利用资源。

扩展ip地址范围

use neutron;
select * from ipallocationpools;
update ipallocationpools set last_ip='172.26.141.240';
select * from ipamallocationpools;
update ipamallocationpools set last_ip='172.26.141.240';

删除一个计算节点

mysql -u root -p
-- 列出所有服务
use nova;
select * from services;
delete  from services where host='recruiting01-OptiPlex-7040';
select * from compute_nodes\G
delete from compute_nodes where hypervisor_hostname='recruiting01-OptiPlex-7040'

use nova_api;
select * from resource_providers;
select * from inventories;
select *,re.name from inventories left join resource_providers as re on re.id=inventories.resource_provider_id;

use neutron;
select * from agents\G
delete from agents where host='recruiting01-OptiPlex-7040' and  binary='neutron-linuxbridge-agent'

安装dashBoard后504超时

遇到问题先找原因，查看apache的日志/var/log/apache2/，发现权限问题

sudo chown -R www-data:www-data /var/lib/openstack-dashboard/secret-key

权限问题解决了，但还是无法正常运行，报504超时错误。

sudo vim /etc/apache2/conf-available/openstack-dashboard.conf
...
## 添加以下行
WSGIApplicationGroup %{GLOBAL}
...
sudo service apache2 reload

参考

实例状态为error

查看日志文档/var/log/nova/nova-compute.log发现如下错误Instance failed network setup after 1 attempt(s)

Failed to allocate the network(s), not rescheduling

如题，新建实例时出现以上错误，查看/var/log/nova/目录下面没有发现什么有价格的信息。网上求助，发现了一个解决方案链接
具体来说，就是修改/etc/nova/nova.conf，在[default]下面添加如下两行配置

vif_plugging_is_fatal: false
vif_plugging_timeout: 0

然后重启各服务

sudo service nova-api restart &&\
sudo service neutron-server restart &&\
sudo  service neutron-linuxbridge-agent restart &&\
sudo  service neutron-dhcp-agent restart &&\
sudo  service neutron-metadata-agent restart