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Cirros VM cannot boot with fixed IP

asked 2016-06-29 05:33:12 -0500

anonymous user


I've a problem to get networking up in Cirros for a my VM, I successfully create network and subnet,

I've got stuck and I'm out of ideas, Please advice on how to get the network up.

neutron net-create ext-net --shared --provider:physical_network public --provider:network_type flat --router:external True

neutron subnet-create ext-net --name ext-subnet --allocation-pool start=,end= --disable-dhcp --gateway; nova boot --flavor m1.tiny --image cirros --nic net-id=46f5797e-443a-4a3a-9069-6f4f98a83a2f,v4-fixed-ip= --security-group default --key-name mykey myinstance

nova list gives:

ca58a237-fd6f-4639-b75a-269594e1b007 | myinstance | ACTIVE | - | Running | ext-net=

neutron net-show 46f5797e-443a-4a3a-9069-6f4f98a83a2f

+---------------------------+--------------------------------------+ | Field | Value | +---------------------------+--------------------------------------+ | admin_state_up | True | | id | 46f5797e-443a-4a3a-9069-6f4f98a83a2f | | mtu | 0 | | name | ext-net | | port_security_enabled | True | | provider:network_type | flat | | provider:physical_network | public | | provider:segmentation_id | | | router:external | True | | shared | True | | status | ACTIVE | | subnets | 5048910b-26c2-4a1d-aa5e-410259c2ca0f | | tenant_id | f60a9b7a639c4594a4854ef4589ae68f

neutron subnet-show 5048910b-26c2-4a1d-aa5e-410259c2ca0f +-------------------+----------------------------------------------------+ | Field | Value | +-------------------+----------------------------------------------------+ | allocation_pools | {"start": "", "end": ""} | | cidr | | | dns_nameservers | | | enable_dhcp | False | | gateway_ip | | | host_routes | | | id | 5048910b-26c2-4a1d-aa5e-410259c2ca0f | | ip_version | 4 | | ipv6_address_mode | | | ipv6_ra_mode | | | name | ext-subnet | | network_id | 46f5797e-443a-4a3a-9069-6f4f98a83a2f | | subnetpool_id | | | tenant_id | f60a9b7a639c4594a4854ef4589ae68f | +-------------------+----------------------------------------------------+

All my nova services, in nova service-list are up. The same goes for neutron-agent list. This is Liberty on CentOS7

3 Controllers

2 Networking nodes

4 Compute nodes

HA as per HA-Guide with HA-proxy


LX93W1dUhkZAR1aKTIRYfqBHFbnpmI86oo/9iNLKfIa8tWe8WF1UsGjp+R7pWf7CSFeym9IO4gAAAIBrutLwVcshECgCSHKGztG8dpnoC/+By30VVKorYridfuz4F8/5N75azv7ayFv8CYHL4FLsyZ0FWBm+NQv0BHzq+6cCMFx79GTT03bn/PQBsuwXNqj0fA5bBsgRvYOe9x+PFHjDZLZ2P7KEdCoL4Dll2vKoWXmDi7U1R+awT/hR/A== root@cirros -----END SSH HOST KEY KEYS----- === network info === if-info: lo,up,,8,::1 if-info: eth0,up,,8,fe80::f816:3eff:fe4b:9ff2 === datasource: None None === === cirros: current=0.3.4 uptime=221.29 === route: fscanf === pinging gateway failed, debugging connection ===

###### debug start

/etc/init.d/sshd start

Starting dropbear sshd: OK route: fscanf

ifconfig -a

eth0 Link encap:Ethernet HWaddr FA:16:3E:4B:9F:F2
inet6 addr: fe80::f816:3eff:fe4b:9ff2/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:395 errors:0 dropped:0 overruns:0 frame:0 TX packets:8 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:27378 (26.7 KiB) TX bytes:1132 (1.1 KiB)

lo Link encap:Local Loopback
inet addr: Mask: inet6 addr: ::1/128 Scope:Host UP LOOPBACK RUNNING MTU:16436 Metric:1 RX packets:12 errors:0 dropped:0 overruns:0 frame:0 TX packets:12 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:1020 (1020.0 B) TX bytes:1020 (1020.0 B)

route -n

Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface route: fscanf

cat /etc/resolv.conf

cat: can't open '/etc/resolv.conf': No such file or directory

gateway not found

/sbin/cirros-status: line 1: can't open /etc/resolv.conf: no such file

pinging nameservers

uname -a

Linux cirros 3.2.0-80-virtual #116-Ubuntu SMP Mon Mar 23 17:28:52 UTC 2015 x86_64 ... (more)

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answered 2016-07-03 15:12:15 -0500

james-denton gravatar image

updated 2016-07-03 15:14:16 -0500


Did you follow the OVS guide or the LinuxBridge guide?

Looks like you may have some Layer 2 issue. With OVS, your provider label 'public' should map to a bridge, and that bridge should in turn be connected to an interface (ie. eth1) that connects to the physical infrastructure. With LinuxBridge, the label should map to a physical interface that will be automatically connected to a bridge that Neutron creates on each host.

You may want to confirm that plumbing is in place and correct across all hosts, as it may be preventing the DHCP namespace on your network nodes from communicating with the instances on your compute nodes.

EDIT: It looks like you disabled DHCP on the subnet during the creation of the subnet. As a result, your instance will not be able to communicate without you logging in an manually through the console and configuring the fixed IP on the interface. Enabling DHCP allows Neutron to handle that for you, provided the instance's interface is configured to use DHCP.

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Asked: 2016-06-29 05:33:12 -0500

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Last updated: Jul 03 '16