Hi Edward,

Here is the official definition of this config option.
# IP address of this host (string value)
#my_ip=10.0.0.1

I think they are used in the same way - as the IP address of the host. It's used in several different places. Below is a rough summary of its usage on both compute and controller nodes.


========================= compute usage =========================
./nova/compute/resource_tracker.py:60:CONF.import_opt('my_ip', 'nova.netconf')
./nova/compute/resource_tracker.py:278:            metrics_info['host_ip'] = CONF.my_ip
./nova/compute/resource_tracker.py:301:        resources['host_ip'] = CONF.my_ip

update resource info in the database - compute_nodes.host_ip


./nova/virt/libvirt/driver.py:266:CONF.import_opt('my_ip', 'nova.netconf')
./nova/virt/libvirt/driver.py:1160:        connector = {'ip': CONF.my_ip,
./nova/virt/libvirt/driver.py:2389:        return CONF.my_ip

used as an argument when terminating a volume connection - volume drivers may or may not use it,
and also used to compare with migration destination host to see if a storage is shared with the destination while migrating disk

./nova/virt/hyperv/hostops.py:32:CONF.import_opt('my_ip', 'nova.netconf')
./nova/virt/hyperv/hostops.py:175:        host_ip = CONF.my_ip

has reference to it, but doesn't seem to use it anymore

./nova/virt/hyperv/volumeops.py:55:CONF.import_opt('my_ip', 'nova.netconf')
./nova/virt/hyperv/volumeops.py:203:            'ip': CONF.my_ip,

used while composing volume connection param dictionary


./nova/virt/baremetal/driver.py:76:CONF.import_opt('my_ip', 'nova.netconf')

has reference to it, but doesn't seem to use it anymore

./nova/virt/baremetal/volume_driver.py:198:            'ip': CONF.my_ip,

used while composing volume connection param dictionary

./nova/virt/baremetal/pxe.py:356:                  'opt_value': CONF.my_ip},
./nova/virt/baremetal/pxe.py:358:                  'opt_value': CONF.my_ip}

used as a option for dhcp while creating an instance

./nova/virt/vmwareapi/vmops.py:70:CONF.import_opt('my_ip', 'nova.netconf')
./nova/virt/vmwareapi/vmops.py:101:            self._base_folder = '%s%s' % (CONF.my_ip,


========================= controller usage =========================

used as part of the base folder name for image cache

./nova/network/linux_net.py:62:               default='$my_ip',
./nova/network/linux_net.py:108:               default='$my_ip',
./nova/network/linux_net.py:138:CONF.import_opt('my_ip', 'nova.netconf')

used as default values for routing_source_ip(Public IP of network host) and metadata_host(The IP address for the metadata API server)

./nova/network/manager.py:108:               default='$my_ip',
./nova/network/manager.py:169:CONF.import_opt('my_ip', 'nova.netconf')

used as default values for vpn_ip(Public IP for the cloudpipe VPN servers)


./nova/image/s3.py:48:               default='$my_ip',
./nova/image/s3.py:71:CONF.import_opt('my_ip', 'nova.netconf')

used as a parameter while creating connection with s3 compatible service - swfit

./nova/image/glance.py:44:               default='$my_ip',
./nova/image/glance.py:76:CONF.import_opt('my_ip', 'nova.netconf')

used as default value of glance_host (Default glance hostname or IP address)

./nova/api/ec2/cloud.py:57:               default='$my_ip',
./nova/api/ec2/cloud.py:60:               default='$my_ip',
./nova/api/ec2/cloud.py:79:CONF.import_opt('my_ip', 'nova.netconf')

used as default value of ec2_host(The IP address of the EC2 API server) and ec2_dmz_host(The internal IP address of the EC2 API server)