network create no longer creates a gateway by default

[ondrejbudai]

Is this a BUG REPORT or FEATURE REQUEST? (leave only one on its own line)

/kind bug

Description

podman network create used to create a default gateway if it wasn't provided. This behavior was removed in 2.2.0, see this diff: e7a72d7#diff-1203e6d536d51fdb4f55e4a605d74cc02986bb5b934027f576dbf8faf91ff6b9L66-L69

Steps to reproduce the issue:

1. podman network create test

2. podman inspect test

Describe the results you received:

[
    {
...
        "plugins": [
            {
                "bridge": "cni-podman1",
                "hairpinMode": true,
                "ipMasq": true,
                "ipam": {
                    "ranges": [
                        [
                            {
                                "subnet": "10.89.0.0/24"
                            }
                        ]
                    ],
...
]

Describe the results you expected:

[
    {
...
        "plugins": [
            {
                "bridge": "cni-podman1",
                "hairpinMode": true,
                "ipMasq": true,
                "ipam": {
                    "ranges": [
                        [
                            {
                                "subnet": "10.89.0.0/24",
                                "gateway": "10.89.0.1"
                            }
                        ]
                    ],
...
]

Output of podman version:

Version:      2.2.1
API Version:  2.1.0
Go Version:   go1.15.5
Built:        Tue Dec  8 15:37:50 2020
OS/Arch:      linux/amd64

Output of podman info --debug:

host:
  arch: amd64
  buildahVersion: 1.18.0
  cgroupManager: systemd
  cgroupVersion: v2
  conmon:
    package: conmon-2.0.21-3.fc33.x86_64
    path: /usr/bin/conmon
    version: 'conmon version 2.0.21, commit: 0f53fb68333bdead5fe4dc5175703e22cf9882ab'
  cpus: 8
  distribution:
    distribution: fedora
    version: "33"
  eventLogger: journald
  hostname: localhost.localdomain
  idMappings:
    gidmap:
    - container_id: 0
      host_id: 1000
      size: 1
    - container_id: 1
      host_id: 100000
      size: 65536
    uidmap:
    - container_id: 0
      host_id: 1000
      size: 1
    - container_id: 1
      host_id: 100000
      size: 65536
  kernel: 5.9.13-200.fc33.x86_64
  linkmode: dynamic
  memFree: 500396032
  memTotal: 16650522624
  ociRuntime:
    name: crun
    package: crun-0.16-1.fc33.x86_64
    path: /usr/bin/crun
    version: |-
      crun version 0.16
      commit: eb0145e5ad4d8207e84a327248af76663d4e50dd
      spec: 1.0.0
      +SYSTEMD +SELINUX +APPARMOR +CAP +SECCOMP +EBPF +YAJL
  os: linux
  remoteSocket:
    path: /run/user/1000/podman/podman.sock
  rootless: true
  slirp4netns:
    executable: /usr/bin/slirp4netns
    package: slirp4netns-1.1.8-1.fc33.x86_64
    version: |-
      slirp4netns version 1.1.8
      commit: d361001f495417b880f20329121e3aa431a8f90f
      libslirp: 4.3.1
      SLIRP_CONFIG_VERSION_MAX: 3
      libseccomp: 2.5.0
  swapFree: 3139600384
  swapTotal: 4294963200
  uptime: 94h 34m 13.45s (Approximately 3.92 days)
registries:
  search:
  - registry.fedoraproject.org
  - registry.access.redhat.com
  - registry.centos.org
  - docker.io
store:
  configFile: /home/obudai/.config/containers/storage.conf
  containerStore:
    number: 0
    paused: 0
    running: 0
    stopped: 0
  graphDriverName: overlay
  graphOptions:
    overlay.mount_program:
      Executable: /usr/bin/fuse-overlayfs
      Package: fuse-overlayfs-1.3.0-1.fc33.x86_64
      Version: |-
        fusermount3 version: 3.9.3
        fuse-overlayfs: version 1.3
        FUSE library version 3.9.3
        using FUSE kernel interface version 7.31
  graphRoot: /home/obudai/.local/share/containers/storage
  graphStatus:
    Backing Filesystem: btrfs
    Native Overlay Diff: "false"
    Supports d_type: "true"
    Using metacopy: "false"
  imageStore:
    number: 12
  runRoot: /run/user/1000/containers
  volumePath: /home/obudai/.local/share/containers/storage/volumes
version:
  APIVersion: 2.1.0
  Built: 1607438270
  BuiltTime: Tue Dec  8 15:37:50 2020
  GitCommit: ""
  GoVersion: go1.15.5
  OsArch: linux/amd64
  Version: 2.2.1

Package info (e.g. output of rpm -q podman or apt list podman):

podman-2.2.1-1.fc33.x86_64

Have you tested with the latest version of Podman and have you checked the Podman Troubleshooting Guide?

Yes

[mheon]

Eeek. This one's pretty bad. @rhatdan @baude I think this one needs to be investigated and fixed for the RHEL 2.2.1 branch.

[baude]

based on the author's comments, it isnt needed:

https://github.com/containers/podman/blob/master/libpod/network/create.go#L156