Tag Archives: openstack

openstack icehouse update errors

最近将Openstack从havana升级到icehouse,总体问题不大,但是还是有点小问题,花了一点时间。

1 密钥过期,keystone的密钥提示过期。

如nova提示:
2014-04-29 10:52:14.074 27081 WARNING keystoneclient.middleware.auth_token [-] Verify error: Command ‘openssl’ returned non-zero exit status 4

解决办法是1) 备份/etc/keystone/ssl目录并删除,运行keystone-manage pki_setup –keystone-user keystone –keystone-group keystone,上面的ssl目录会生成,这里的用户名和用户组为linux系统中的keystone对应的用户和组 3) 修改ssl目录属主和权限700.

neutron也可能由此提示,解决办法是删除/var/lib/neutron/keystone-signing目录,并重启neutron-server。

此外,可能还需要删除/tmp下的keystone-signing-xxxxx目录。

总体而言,上面的错误表面现象为keystone 401 Unauthorized的错误,但是解决问题需要定位到相应模块,用debug=true和verbose=true从调试信息中找出问题。

如nova list返回401的原因有可能是neutron的证书问题,所以大家在调错是一定要仔细。

2 数据库升级,这个也不算是问题,只是每个模块升级的时候几乎都要升级数据库,如 keystone-manage db_sync等。

neutron中一种常见网络不通的现象,附修复脚本

neutron中经常发现vm ping不通网关,我发现很多情况是因为ovs-plugin没有将qvb连接到qbr桥上,所以解决办法也很简单,就是将其连上,即将qbr设为master。

具体的neutron、ovs、veth和iptables等就不展开讲了,具体可以看下图

ovs-neutron

当一个vm启动或被硬重启之后,tap接口(当使用gre模式时为tap)和qbr桥会被自动创建,而且tap的master为qbr。理论上qvb的master也应该是qbr,但我经常发现这个link的master没有被设置。那么设置脚本就很简单了:

#!/bin/bash

LINKS=`ip link|grep qvb |awk '{print $2}' |sed s'/.$//'|sed s'/^...//'`
for LINK in $LINKS
do
# a qbr link should appear after hard reboot an instance
ip link set "qbr$LINK" up
echo ip link set "qvb$LINK" master "qbr$LINK"
ip link set "qvb$LINK" master "qbr$LINK"
echo ip link set "tap$LINK" master "qbr$LINK"
ip link set "tap$LINK" master "qbr$LINK"
done

此外在SDN环境中还有几种vm连不上可能,比如

  1. br-tun每次在ovs-agent重启后controller就会消失,此时应该在重启脚本中添加:  ovs-vsctl set-controller br-tun tcp:30.0.0.1
  2. 确定br-int和br-tun没有多余的流,用ovs-ofctl dump-flows br-int/br-tun可看
  3. 确定网络控制器正常运行,有时候监控of控制流发现只有packet_in没有packet_out,此时重启一下网络控制器可能会解决问题

如果还是有问题,不妨对照上面的连接图,然后分别用tcpdump监听compute node的tap、qbr、qvb、qvo、br-int、br-tun、br-tun所对应的eth(如果用gre模式监听要加参数proto gre才能解gre包),再到network node的eth、br-tun、br-int、再到namespace的网关接口qr-xxx。

如果发现br-int有数据包,但br-tun没有数据包,不妨监听一下openflow的控制流:ovs-ofctl snoop br-int/br-tun,看看控制器的响应如

[openstack]NAT gateway和port不一致导致VM不能到外网

当VM设置完floatingip后,VM还是不能连接外网,排查原因,发现是quantum中设置的问题:

quantum中设置外网为192.168.19.129/25,不设网关,allocation_pools为{“start”: “192.168.19.130”, “end”: “192.168.19.254”}。

root@controller:/usr/src/nova# ip netns exec qrouter-b4721d20-9d39-4d4d-9c37-f18ecb460d02 route -n
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
0.0.0.0 192.168.19.129 0.0.0.0 UG 0 0 0 qg-29c30020-2e
10.0.0.0 0.0.0.0 255.255.255.0 U 0 0 0 qr-cd728374-d8
10.0.1.0 0.0.0.0 255.255.255.0 U 0 0 0 qr-f915c799-96
192.168.19.128 0.0.0.0 255.255.255.128 U 0 0 0 qg-29c30020-2e

路由器的网卡却是:

root@controller:/usr/src/nova# ip netns exec qrouter-b4721d20-9d39-4d4d-9c37-f18ecb460d02 ifconfig
lo        Link encap:Local Loopback  
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:16436  Metric:1
          RX packets:14 errors:0 dropped:0 overruns:0 frame:0
          TX packets:14 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:1390 (1.3 KB)  TX bytes:1390 (1.3 KB)

qg-29c30020-2e Link encap:Ethernet  HWaddr fa:16:3e:10:18:21  
          inet addr:192.168.19.130  Bcast:192.168.19.255  Mask:255.255.255.128
          inet6 addr: fe80::f816:3eff:fe10:1821/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:87 errors:0 dropped:0 overruns:0 frame:0
          TX packets:67 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:12593 (12.5 KB)  TX bytes:9608 (9.6 KB)

qr-cd728374-d8 Link encap:Ethernet  HWaddr fa:16:3e:d7:5a:2f  
          inet addr:10.0.0.1  Bcast:10.0.0.255  Mask:255.255.255.0
          inet6 addr: fe80::f816:3eff:fed7:5a2f/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:64 errors:0 dropped:0 overruns:0 frame:0
          TX packets:89 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:9710 (9.7 KB)  TX bytes:10627 (10.6 KB)

qr-f915c799-96 Link encap:Ethernet  HWaddr fa:16:3e:96:89:3a  
          inet addr:10.0.1.1  Bcast:10.0.1.255  Mask:255.255.255.0
          inet6 addr: fe80::f816:3eff:fe96:893a/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:9 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:0 (0.0 B)  TX bytes:594 (594.0 B)

这两个值是不同的,本应从192.168.19.130路由的数据包均发往192.168.19.129,导致VM无法出去。其实后者是quantum中与外网连接的port中的fixed_ips值:

+--------------------------------------+------+-------------------+---------------------------------------------------------------------------------------+
| id                                   | name | mac_address       | fixed_ips                                                                             |
+--------------------------------------+------+-------------------+---------------------------------------------------------------------------------------+
| 10d13e25-cc01-4edc-aba4-5e2b3a6dff80 |      | fa:16:3e:e6:9e:30 | {"subnet_id": "169ad3b8-c961-4128-b053-2d6d36afbe1f", "ip_address": "10.0.0.4"}       |
| 29c30020-2e91-4ffa-91e3-a8acef553641 |      | fa:16:3e:10:18:21 | {"subnet_id": "3f53264f-683b-45a8-a7ab-289afd2288b5", "ip_address": "192.168.19.130"} |
| 7e659611-43b3-4f52-b392-28ddd5051bca |      | fa:16:3e:9e:84:c8 | {"subnet_id": "3f53264f-683b-45a8-a7ab-289afd2288b5", "ip_address": "192.168.19.131"} |
| 7f000789-2e36-4aef-8d08-acb700ddde9f |      | fa:16:3e:07:92:81 | {"subnet_id": "169ad3b8-c961-4128-b053-2d6d36afbe1f", "ip_address": "10.0.0.2"}       |
| 91da98b9-e9df-4a2c-b97d-02299d33fe89 |      | fa:16:3e:f7:42:d9 | {"subnet_id": "3f53264f-683b-45a8-a7ab-289afd2288b5", "ip_address": "192.168.19.132"} |
| a132b58c-238a-4b9f-92ce-c47521cda668 |      | fa:16:3e:31:81:8e | {"subnet_id": "169ad3b8-c961-4128-b053-2d6d36afbe1f", "ip_address": "10.0.0.3"}       |
| b1a9afa6-6850-4044-a2b6-cca6c12fc6fa |      | fa:16:3e:89:2e:fb | {"subnet_id": "0636c5f2-70ab-4fb9-a7d5-986c92eaf1aa", "ip_address": "10.0.1.2"}       |
| b629349e-ad6e-427a-8aae-291f55ef4b32 |      | fa:16:3e:31:a2:cf | {"subnet_id": "169ad3b8-c961-4128-b053-2d6d36afbe1f", "ip_address": "10.0.0.5"}       |
| cd728374-d89e-4f64-b437-b3e1580b49e9 |      | fa:16:3e:d7:5a:2f | {"subnet_id": "169ad3b8-c961-4128-b053-2d6d36afbe1f", "ip_address": "10.0.0.1"}       |
| f915c799-96aa-40bf-a3aa-06d43bc1c284 |      | fa:16:3e:96:89:3a | {"subnet_id": "0636c5f2-70ab-4fb9-a7d5-986c92eaf1aa", "ip_address": "10.0.1.1"}       |
+--------------------------------------+------+-------------------+---------------------------------------------------------------------------------------+

如果设置该网络的网关为130,提示失败:

# quantum subnet-update userA-public --gateway_ip 192.168.19.130
Gateway ip 192.168.19.130 conflicts with allocation pool 192.168.19.130-192.168.19.254

在quantum代码中体现是:
agent/l3_agent.py

        ex_gw_ip = ex_gw_port['fixed_ips'][0]['ip_address']
        if not ip_lib.device_exists(interface_name,
                                    root_helper=self.root_helper,
                                    namespace=ri.ns_name()):
            
......

        gw_ip = ex_gw_port['subnet']['gateway_ip']
        if ex_gw_port['subnet']['gateway_ip']:
            cmd = ['route', 'add', 'default', 'gw', gw_ip]

不知道为什么这里有两个:ex_gw_ip和gw_ip,不一致导致这个问题。

workaround很简单:

# ip netns exec qrouter-b4721d20-9d39-4d4d-9c37-f18ecb460d02 route del default gw 192.168.19.129
# ip netns exec qrouter-b4721d20-9d39-4d4d-9c37-f18ecb460d02 route add default gw 192.168.19.130

——————————我是分割线——————————————–
上面的workaround很是麻烦,每次重启l3agent都需要添加,我今天看了一下这个问题,其实还是因为我们对neutron网络不太理解造成的。我前面的方法是先将数据包扔到qg-f103a9f2-d6接口,然后在命名空间外的路由表中进行路由决策:

# ip netns exec qrouter-09be29ea-25f6-4a53-b3ab-8d0e13dc7198 route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
0.0.0.0         192.168.19.130  0.0.0.0         UG    0      0        0 qg-f103a9f2-d6
100.0.0.0       0.0.0.0         255.255.255.0   U     0      0        0 qr-d8fcb028-ea
192.168.19.0    0.0.0.0         255.255.255.0   U     0      0        0 qg-f103a9f2-d6
200.0.0.0       0.0.0.0         255.255.255.0   U     0      0        0 qr-b422c431-d8

# route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
0.0.0.0         192.168.19.254  0.0.0.0         UG    100    0        0 br-ex
20.0.0.0        0.0.0.0         255.255.255.0   U     0      0        0 eth1
30.0.0.0        0.0.0.0         255.255.255.0   U     0      0        0 eth2
192.168.19.0    0.0.0.0         255.255.255.0   U     0      0        0 br-ex

数据包的流向是qr-d8fcb028-ea->(namespace routing)->qg-f103a9f2-d6->(routing)->br-ex->eth0->router

其实public-net本身就是一个外网,所以应该跟物理机的网络一致,也就是192.168.19.0/24,网关是物理网关192.168.19.254。这样,每次l3agent都会在命名空间中新建默认路由:

# ip netns exec qrouter-09be29ea-25f6-4a53-b3ab-8d0e13dc7198 route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
0.0.0.0         192.168.19.254  0.0.0.0         UG    0      0        0 qg-f103a9f2-d6
100.0.0.0       0.0.0.0         255.255.255.0   U     0      0        0 qr-d8fcb028-ea
192.168.19.0    0.0.0.0         255.255.255.0   U     0      0        0 qg-f103a9f2-d6
200.0.0.0       0.0.0.0         255.255.255.0   U     0      0        0 qr-b422c431-d8

这样数据包到了这个命名空间后,直接经过路由决策从qg-f103a9f2-d6经过br-ex到eth0出去了。虽然数据包流向与前面的一样,但是从命名空间到物理网关还是在一个网络中流动。

VM上不了网的一个原因

Openstack中VM上不了网有很多原因,今天遇到一个,其实之前也遇到过,只是不熟了才调试了半天,悲剧。。。

现象:VM联网速度很慢,例如apt-get update能连上主机,但是半天下载不了多少东西

调试:因为VM能上网,所以开始以为是quantum的l3问题,在命名空间下查看iptables和route,均没有问题。。
root@controller:/usr/src/nova# ip netns
qdhcp-eb2fc4cd-d656-4e64-adc2-001d3cfbcebd
qrouter-b4721d20-9d39-4d4d-9c37-f18ecb460d02
qdhcp-77a8d872-103a-4d8c-9f47-bc6ec34a2ff4
qdhcp-faacf658-dae9-4230-8fbc-7cde47c425b1

然后用抓包:
ip netns exec qrouter-b4721d20-9d39-4d4d-9c37-f18ecb460d02 tcpdump -i qg-29c30020-2e (外网网卡)
15:20:00.465882 IP 192.168.19.131 > likho.canonical.com: ICMP 192.168.19.131 unreachable – need to frag (mtu 1454), length 556
15:20:02.046704 IP likho.canonical.com.http > 192.168.19.131.56147: Flags [.], seq 1:1449, ack 256, win 61, options [nop,nop,TS val 3517237056 ecr 105897], length 1448
15:20:02.046825 IP 192.168.19.131 > likho.canonical.com: ICMP 192.168.19.131 unreachable – need to frag (mtu 1454), length 556
ip netns exec qrouter-b4721d20-9d39-4d4d-9c37-f18ecb460d02 tcpdump -i qr-cd728374-d8 (内网网卡)
15:20:02.046763 IP likho.canonical.com.http > 10.0.0.4.56147: Flags [.], seq 1:1449, ack 256, win 61, options [nop,nop,TS val 3517237056 ecr 105897], length 1448
15:20:02.046800 IP 10.0.0.4 > likho.canonical.com: ICMP 10.0.0.4 unreachable – need to frag (mtu 1454), length 556
15:20:02.541472 IP sudice.canonical.com.http > 10.0.0.4.39679: Flags [.], seq 1:1449, ack 258, win 61, options [nop,nop,TS val 1537132828 ecr 105323], length 1448
15:20:02.541502 IP 10.0.0.4 > sudice.canonical.com: ICMP 10.0.0.4 unreachable – need to frag (mtu 1454), length 556
发现出现很多unreachable的问题,开始以为是内网没经过SNAT出去,后来才发现错误信息重点是need to frag

原因是VM的MTU太小了,需要设置一个大一些的值,那么处理就很简单了,直接在VM中运行:
ifconfig eth0 mtu 1400

DONE