Public bug reported: This is a follow on from https://bugs.launchpad.net/ubuntu/+source /cloud-init/+bug/1802073 + its fix in: https://git.launchpad.net/cloud- init/commit/?id=0bb4c74e
After a clean launch of Ubuntu 18.04.2 on a t3.small AWS EC2 instance, in a VPC in the eu-west-1 region, we can see the following: ---snip--- root@ip-172-31-23-210:~# cat /etc/os-release NAME="Ubuntu" VERSION="18.04.2 LTS (Bionic Beaver)" ID=ubuntu ID_LIKE=debian PRETTY_NAME="Ubuntu 18.04.2 LTS" VERSION_ID="18.04" HOME_URL="https://www.ubuntu.com/" SUPPORT_URL="https://help.ubuntu.com/" BUG_REPORT_URL="https://bugs.launchpad.net/ubuntu/" PRIVACY_POLICY_URL="https://www.ubuntu.com/legal/terms-and-policies/privacy-policy" VERSION_CODENAME=bionic UBUNTU_CODENAME=bionic root@ip-172-31-23-210:~# dpkg -l | grep '\(cloud-init.*\|netplan.*\|ifupdown\)' ii cloud-init 18.4-0ubuntu1~18.04.1 all Init scripts for cloud instances ii cloud-initramfs-copymods 0.40ubuntu1.1 all copy initramfs modules into root filesystem for later use ii cloud-initramfs-dyn-netconf 0.40ubuntu1.1 all write a network interface file in /run for BOOTIF ii netplan.io 0.40.1~18.04.4 amd64 YAML network configuration abstraction for various backends root@ip-172-31-23-210:~# cat /etc/netplan/50-cloud-init.yaml # This file is generated from information provided by # the datasource. Changes to it will not persist across an instance. # To disable cloud-init's network configuration capabilities, write a file # /etc/cloud/cloud.cfg.d/99-disable-network-config.cfg with the following: # network: {config: disabled} network: version: 2 ethernets: ens5: dhcp4: true match: macaddress: 06:bd:10:32:ce:7e set-name: ens5 root@ip-172-31-23-210:~# root@ip-172-31-23-210:~# ip addr 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000 link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 inet 127.0.0.1/8 scope host lo valid_lft forever preferred_lft forever inet6 ::1/128 scope host valid_lft forever preferred_lft forever 2: ens5: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 9001 qdisc mq state UP group default qlen 1000 link/ether 06:bd:10:32:ce:7e brd ff:ff:ff:ff:ff:ff inet 172.31.23.210/20 brd 172.31.31.255 scope global dynamic ens5 valid_lft 3510sec preferred_lft 3510sec inet6 fe80::4bd:10ff:fe32:ce7e/64 scope link valid_lft forever preferred_lft forever root@ip-172-31-23-210:~# ---snip--- At this point, I installed all OS updates via: apt-get clean;apt-get update;apt-get dist-upgrade; I rebooted the machine and checked the version of packages now installed: ---snip--- root@ip-172-31-23-210:~# dpkg -l | grep '\(cloud-init.*\|netplan.*\|ifupdown\)' ii cloud-init 18.5-45-g3554ffe8-0ubuntu1~18.04.1 all Init scripts for cloud instances ii cloud-initramfs-copymods 0.40ubuntu1.1 all copy initramfs modules into root filesystem for later use ii cloud-initramfs-dyn-netconf 0.40ubuntu1.1 all write a network interface file in /run for BOOTIF ii netplan.io 0.96-0ubuntu0.18.04.4 amd64 YAML network configuration abstraction for various backends ---snip--- 1. The contents of the /etc/netplan/50-cloud-init.yaml file remained the same as above after OS updates. 2. This means that if this machine is powered off and an AMI taken of it, any new EC2 instances launched from that AMI will not have a working network since the mac address of the new EC2 instances will not match the "macaddress" line in the /etc/netplan/50-cloud-init.yaml file. 3. This happens because the mac address of a VPC EC2 instance is tied to the ENI associated to the EC2 instance. 4. When a new instance is launched from the capture AMI, it will get a new ENI and hence a new MAC address. So although the network configuration file should be regenerated at first boot in the newly launched instance, this currently doesn't happen. I do not know why. ** Affects: cloud-init (Ubuntu) Importance: Undecided Status: New -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1828622 Title: No network in AWS (VPC EC2 instance) after launching an instance from an AMI captured earlier To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/cloud-init/+bug/1828622/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs