root $ root $ docker run --name alice --network foo -p 3307:3307 -tide MYSQL_ROOT_PASSWORD=password mysql/mysql-server:latest 7041df2ca8230d1cd6b6dc2b40bbb2fab336caf32aa8ddb7b257be13ed5fc60d root $ root $ docker run --name bob --network foo -p 3308:3308 -tide MYSQL_ROOT_PASSWORD=password mysql/mysql-server:latest f0c0ffa9ee26ea67d7f4f9352ed46c05871c9600787985f10bbe3586e2601f4f root $ root $ docker network inspect foo [ { "Name": "foo", "Id": "94f944a05b0ee66779ee469faa84a53a7db19262cf5c4a234268081153512e5c", "Created": "2020-09-26T14:34:15.968639841-07:00", "Scope": "local", "Driver": "bridge", "EnableIPv6": false, "IPAM": { "Driver": "default", "Options": {}, "Config": [ { "Subnet": "172.21.0.0/16", "Gateway": "172.21.0.1" } ] }, "Internal": false, "Attachable": false, "Ingress": false, "ConfigFrom": { "Network": "" }, "ConfigOnly": false, "Containers": { "7041df2ca8230d1cd6b6dc2b40bbb2fab336caf32aa8ddb7b257be13ed5fc60d": { "Name": "alice", "EndpointID": "5feea1c8cd5bcf2f126812ddb9c687a67e185aeab5e25c33128f57d95d5ea713", "MacAddress": "02:42:ac:15:00:02", "IPv4Address": "172.21.0.2/16", "IPv6Address": "" }, "f0c0ffa9ee26ea67d7f4f9352ed46c05871c9600787985f10bbe3586e2601f4f": { "Name": "bob", "EndpointID": "325b4ef28034b1baa0b99958f1e64c92fc3dd083b17228233f974e907f57d81a", "MacAddress": "02:42:ac:15:00:03", "IPv4Address": "172.21.0.3/16", "IPv6Address": "" } }, "Options": {}, "Labels": {} } ] root $ root $ docker exec -it alice bash bash-4.2# bash-4.2# whoami root bash-4.2# bash-4.2# yum install -y iputils Loaded plugins: ovl mysql-connectors-community | 2.5 kB 00:00:00 mysql-tools-community | 2.5 kB 00:00:00 mysql80-community | 2.5 kB 00:00:00 mysql80-server-minimal | 2.5 kB 00:00:00 ol7_latest | 2.7 kB 00:00:00 (1/4): mysql80-server-minimal/x86_64/primary_db | 19 kB 00:00:00 (2/4): mysql-tools-community/x86_64/primary_db | 76 kB 00:00:00 (3/4): mysql-connectors-community/x86_64/primary_db | 62 kB 00:00:00 (4/4): mysql80-community/x86_64/primary_db | 115 kB 00:00:01 (1/3): ol7_latest/x86_64/group | 660 kB 00:00:02 (2/3): ol7_latest/x86_64/updateinfo | 2.9 MB 00:00:09 (3/3): ol7_latest/x86_64/primary_db | 36 MB 00:01:07 Resolving Dependencies --> Running transaction check ---> Package iputils.x86_64 0:20160308-10.el7 will be installed --> Processing Dependency: systemd for package: iputils-20160308-10.el7.x86_64 --> Running transaction check ---> Package systemd.x86_64 0:219-73.0.3.el7_8.9 will be installed --> Processing Dependency: systemd-libs = 219-73.0.3.el7_8.9 for package: systemd-219-73.0.3.el7_8.9.x86_64 --> Processing Dependency: kmod >= 18-4 for package: systemd-219-73.0.3.el7_8.9.x86_64 --> Processing Dependency: dbus for package: systemd-219-73.0.3.el7_8.9.x86_64 --> Processing Dependency: acl for package: systemd-219-73.0.3.el7_8.9.x86_64 --> Processing Dependency: libcryptsetup.so.12(CRYPTSETUP_2.0)(64bit) for package: systemd-219-73.0.3.el7_8.9.x86_64 --> Processing Dependency: libkmod.so.2(LIBKMOD_5)(64bit) for package: systemd-219-73.0.3.el7_8.9.x86_64 --> Processing Dependency: libdw.so.1(ELFUTILS_0.122)(64bit) for package: systemd-219-73.0.3.el7_8.9.x86_64 --> Processing Dependency: libdw.so.1(ELFUTILS_0.158)(64bit) for package: systemd-219-73.0.3.el7_8.9.x86_64 --> Processing Dependency: libdw.so.1(ELFUTILS_0.130)(64bit) for package: systemd-219-73.0.3.el7_8.9.x86_64 --> Processing Dependency: liblz4.so.1()(64bit) for package: systemd-219-73.0.3.el7_8.9.x86_64 --> Processing Dependency: libdw.so.1()(64bit) for package: systemd-219-73.0.3.el7_8.9.x86_64 --> Processing Dependency: libkmod.so.2()(64bit) for package: systemd-219-73.0.3.el7_8.9.x86_64 --> Processing Dependency: libcryptsetup.so.12()(64bit) for package: systemd-219-73.0.3.el7_8.9.x86_64 --> Processing Dependency: libqrencode.so.3()(64bit) for package: systemd-219-73.0.3.el7_8.9.x86_64 --> Running transaction check ---> Package acl.x86_64 0:2.2.51-15.el7 will be installed ---> Package cryptsetup-libs.x86_64 0:2.0.3-6.el7 will be installed --> Processing Dependency: libdevmapper.so.1.02(Base)(64bit) for package: cryptsetup-libs-2.0.3-6.el7.x86_64 --> Processing Dependency: libdevmapper.so.1.02(DM_1_02_97)(64bit) for package: cryptsetup-libs-2.0.3-6.el7.x86_64 --> Processing Dependency: libdevmapper.so.1.02()(64bit) for package: cryptsetup-libs-2.0.3-6.el7.x86_64 --> Processing Dependency: libjson-c.so.2()(64bit) for package: cryptsetup-libs-2.0.3-6.el7.x86_64 ---> Package dbus.x86_64 1:1.10.24-14.0.1.el7_8 will be installed --> Processing Dependency: dbus-libs(x86-64) = 1:1.10.24-14.0.1.el7_8 for package: 1:dbus-1.10.24-14.0.1.el7_8.x86_64 --> Processing Dependency: libdbus-1.so.3(LIBDBUS_PRIVATE_1.10.24)(64bit) for package: 1:dbus-1.10.24-14.0.1.el7_8.x86_64 --> Processing Dependency: libdbus-1.so.3(LIBDBUS_1_3)(64bit) for package: 1:dbus-1.10.24-14.0.1.el7_8.x86_64 --> Processing Dependency: libdbus-1.so.3()(64bit) for package: 1:dbus-1.10.24-14.0.1.el7_8.x86_64 ---> Package elfutils-libs.x86_64 0:0.176-4.el7 will be installed --> Processing Dependency: default-yama-scope for package: elfutils-libs-0.176-4.el7.x86_64 ---> Package kmod.x86_64 0:20-28.0.3.el7 will be installed --> Processing Dependency: /usr/bin/xz for package: kmod-20-28.0.3.el7.x86_64 --> Processing Dependency: /usr/bin/nm for package: kmod-20-28.0.3.el7.x86_64 --> Processing Dependency: dracut for package: kmod-20-28.0.3.el7.x86_64 ---> Package kmod-libs.x86_64 0:20-28.0.3.el7 will be installed ---> Package lz4.x86_64 0:1.7.5-3.el7 will be installed ---> Package qrencode-libs.x86_64 0:3.4.1-3.el7 will be installed ---> Package systemd-libs.x86_64 0:219-73.0.3.el7_8.9 will be installed --> Running transaction check ---> Package binutils.x86_64 0:2.27-43.base.0.1.el7_8.1 will be installed ---> Package dbus-libs.x86_64 1:1.10.24-14.0.1.el7_8 will be installed ---> Package device-mapper-libs.x86_64 7:1.02.164-7.0.1.el7_8.2 will be installed --> Processing Dependency: device-mapper = 7:1.02.164-7.0.1.el7_8.2 for package: 7:device-mapper-libs-1.02.164-7.0.1.el7_8.2.x86_64 ---> Package dracut.x86_64 0:033-568.0.3.el7 will be installed --> Processing Dependency: util-linux >= 2.21 for package: dracut-033-568.0.3.el7.x86_64 --> Processing Dependency: /usr/bin/pkg-config for package: dracut-033-568.0.3.el7.x86_64 --> Processing Dependency: kpartx for package: dracut-033-568.0.3.el7.x86_64 --> Processing Dependency: tar for package: dracut-033-568.0.3.el7.x86_64 --> Processing Dependency: procps-ng for package: dracut-033-568.0.3.el7.x86_64 --> Processing Dependency: hardlink for package: dracut-033-568.0.3.el7.x86_64 ---> Package elfutils-default-yama-scope.noarch 0:0.176-4.el7 will be installed ---> Package json-c.x86_64 0:0.11-4.el7_0 will be installed ---> Package xz.x86_64 0:5.2.2-1.el7 will be installed --> Running transaction check ---> Package device-mapper.x86_64 7:1.02.164-7.0.1.el7_8.2 will be installed ---> Package hardlink.x86_64 1:1.0-19.el7 will be installed ---> Package kpartx.x86_64 0:0.4.9-131.0.1.el7 will be installed ---> Package pkgconfig.x86_64 1:0.27.1-4.el7 will be installed ---> Package procps-ng.x86_64 0:3.3.10-27.el7 will be installed ---> Package tar.x86_64 2:1.26-35.el7 will be installed ---> Package util-linux.x86_64 0:2.23.2-63.0.1.el7 will be installed --> Processing Dependency: libsmartcols = 2.23.2-63.0.1.el7 for package: util-linux-2.23.2-63.0.1.el7.x86_64 --> Processing Dependency: libutempter.so.0(UTEMPTER_1.1)(64bit) for package: util-linux-2.23.2-63.0.1.el7.x86_64 --> Processing Dependency: libsmartcols.so.1(SMARTCOLS_2.25)(64bit) for package: util-linux-2.23.2-63.0.1.el7.x86_64 --> Processing Dependency: libutempter.so.0()(64bit) for package: util-linux-2.23.2-63.0.1.el7.x86_64 --> Processing Dependency: libsmartcols.so.1()(64bit) for package: util-linux-2.23.2-63.0.1.el7.x86_64 --> Processing Dependency: libuser.so.1()(64bit) for package: util-linux-2.23.2-63.0.1.el7.x86_64 --> Running transaction check ---> Package libsmartcols.x86_64 0:2.23.2-63.0.1.el7 will be installed ---> Package libuser.x86_64 0:0.60-9.el7 will be installed ---> Package libutempter.x86_64 0:1.1.6-4.el7 will be installed --> Finished Dependency Resolution Dependencies Resolved ==================================================================================================================================== Package Arch Version Repository Size ==================================================================================================================================== Installing: iputils x86_64 20160308-10.el7 ol7_latest 147 k Installing for dependencies: acl x86_64 2.2.51-15.el7 ol7_latest 81 k binutils x86_64 2.27-43.base.0.1.el7_8.1 ol7_latest 5.9 M cryptsetup-libs x86_64 2.0.3-6.el7 ol7_latest 338 k dbus x86_64 1:1.10.24-14.0.1.el7_8 ol7_latest 245 k dbus-libs x86_64 1:1.10.24-14.0.1.el7_8 ol7_latest 169 k device-mapper x86_64 7:1.02.164-7.0.1.el7_8.2 ol7_latest 295 k device-mapper-libs x86_64 7:1.02.164-7.0.1.el7_8.2 ol7_latest 324 k dracut x86_64 033-568.0.3.el7 ol7_latest 330 k elfutils-default-yama-scope noarch 0.176-4.el7 ol7_latest 32 k elfutils-libs x86_64 0.176-4.el7 ol7_latest 290 k hardlink x86_64 1:1.0-19.el7 ol7_latest 14 k json-c x86_64 0.11-4.el7_0 ol7_latest 30 k kmod x86_64 20-28.0.3.el7 ol7_latest 125 k kmod-libs x86_64 20-28.0.3.el7 ol7_latest 53 k kpartx x86_64 0.4.9-131.0.1.el7 ol7_latest 80 k libsmartcols x86_64 2.23.2-63.0.1.el7 ol7_latest 141 k libuser x86_64 0.60-9.el7 ol7_latest 400 k libutempter x86_64 1.1.6-4.el7 ol7_latest 24 k lz4 x86_64 1.7.5-3.el7 ol7_latest 98 k pkgconfig x86_64 1:0.27.1-4.el7 ol7_latest 53 k procps-ng x86_64 3.3.10-27.el7 ol7_latest 290 k qrencode-libs x86_64 3.4.1-3.el7 ol7_latest 49 k systemd x86_64 219-73.0.3.el7_8.9 ol7_latest 5.1 M systemd-libs x86_64 219-73.0.3.el7_8.9 ol7_latest 417 k tar x86_64 2:1.26-35.el7 ol7_latest 845 k util-linux x86_64 2.23.2-63.0.1.el7 ol7_latest 2.0 M xz x86_64 5.2.2-1.el7 ol7_latest 228 k Transaction Summary ==================================================================================================================================== Install 1 Package (+27 Dependent packages) Total download size: 18 M Installed size: 69 M Downloading packages: (1/28): acl-2.2.51-15.el7.x86_64.rpm | 81 kB 00:00:01 (2/28): cryptsetup-libs-2.0.3-6.el7.x86_64.rpm | 338 kB 00:00:02 (3/28): dbus-1.10.24-14.0.1.el7_8.x86_64.rpm | 245 kB 00:00:01 (4/28): dbus-libs-1.10.24-14.0.1.el7_8.x86_64.rpm | 169 kB 00:00:00 (5/28): device-mapper-1.02.164-7.0.1.el7_8.2.x86_64.rpm | 295 kB 00:00:01 (6/28): device-mapper-libs-1.02.164-7.0.1.el7_8.2.x86_64.rpm | 324 kB 00:00:02 (7/28): dracut-033-568.0.3.el7.x86_64.rpm | 330 kB 00:00:01 (8/28): elfutils-default-yama-scope-0.176-4.el7.noarch.rpm | 32 kB 00:00:00 (9/28): binutils-2.27-43.base.0.1.el7_8.1.x86_64.rpm | 5.9 MB 00:00:12 (10/28): hardlink-1.0-19.el7.x86_64.rpm | 14 kB 00:00:00 (11/28): iputils-20160308-10.el7.x86_64.rpm | 147 kB 00:00:00 (12/28): json-c-0.11-4.el7_0.x86_64.rpm | 30 kB 00:00:00 (13/28): kmod-20-28.0.3.el7.x86_64.rpm | 125 kB 00:00:00 (14/28): elfutils-libs-0.176-4.el7.x86_64.rpm | 290 kB 00:00:01 (15/28): kmod-libs-20-28.0.3.el7.x86_64.rpm | 53 kB 00:00:00 (16/28): libsmartcols-2.23.2-63.0.1.el7.x86_64.rpm | 141 kB 00:00:00 (17/28): kpartx-0.4.9-131.0.1.el7.x86_64.rpm | 80 kB 00:00:00 (18/28): libutempter-1.1.6-4.el7.x86_64.rpm | 24 kB 00:00:00 (19/28): libuser-0.60-9.el7.x86_64.rpm | 400 kB 00:00:00 (20/28): lz4-1.7.5-3.el7.x86_64.rpm | 98 kB 00:00:00 (21/28): pkgconfig-0.27.1-4.el7.x86_64.rpm | 53 kB 00:00:00 (22/28): qrencode-libs-3.4.1-3.el7.x86_64.rpm | 49 kB 00:00:00 (23/28): procps-ng-3.3.10-27.el7.x86_64.rpm | 290 kB 00:00:01 (24/28): systemd-libs-219-73.0.3.el7_8.9.x86_64.rpm | 417 kB 00:00:01 (25/28): tar-1.26-35.el7.x86_64.rpm | 845 kB 00:00:04 (26/28): systemd-219-73.0.3.el7_8.9.x86_64.rpm | 5.1 MB 00:00:12 (27/28): xz-5.2.2-1.el7.x86_64.rpm | 228 kB 00:00:00 (28/28): util-linux-2.23.2-63.0.1.el7.x86_64.rpm | 2.0 MB 00:00:07 ------------------------------------------------------------------------------------------------------------------------------------ Total 623 kB/s | 18 MB 00:00:29 Running transaction check Running transaction test Transaction test succeeded Running transaction Installing : xz-5.2.2-1.el7.x86_64 1/28 Installing : lz4-1.7.5-3.el7.x86_64 2/28 Installing : libutempter-1.1.6-4.el7.x86_64 3/28 Installing : 1:hardlink-1.0-19.el7.x86_64 4/28 Installing : libuser-0.60-9.el7.x86_64 5/28 Installing : kmod-libs-20-28.0.3.el7.x86_64 6/28 Installing : json-c-0.11-4.el7_0.x86_64 7/28 Installing : qrencode-libs-3.4.1-3.el7.x86_64 8/28 Installing : binutils-2.27-43.base.0.1.el7_8.1.x86_64 9/28 install-info: /usr/share/info/dir: could not read (No such file or directory) and could not create (No such file or directory) install-info: /usr/share/info/dir: could not read (No such file or directory) and could not create (No such file or directory) install-info: /usr/share/info/dir: could not read (No such file or directory) and could not create (No such file or directory) install-info: /usr/share/info/dir: could not read (No such file or directory) and could not create (No such file or directory) install-info: /usr/share/info/dir: could not read (No such file or directory) and could not create (No such file or directory) Installing : libsmartcols-2.23.2-63.0.1.el7.x86_64 10/28 Installing : 2:tar-1.26-35.el7.x86_64 11/28 Installing : 1:pkgconfig-0.27.1-4.el7.x86_64 12/28 Installing : acl-2.2.51-15.el7.x86_64 13/28 Installing : util-linux-2.23.2-63.0.1.el7.x86_64 14/28 Installing : procps-ng-3.3.10-27.el7.x86_64 15/28 Installing : kpartx-0.4.9-131.0.1.el7.x86_64 16/28 Installing : 7:device-mapper-1.02.164-7.0.1.el7_8.2.x86_64 17/28 Installing : 7:device-mapper-libs-1.02.164-7.0.1.el7_8.2.x86_64 18/28 Installing : cryptsetup-libs-2.0.3-6.el7.x86_64 19/28 Installing : dracut-033-568.0.3.el7.x86_64 20/28 Installing : kmod-20-28.0.3.el7.x86_64 21/28 Installing : elfutils-libs-0.176-4.el7.x86_64 22/28 Installing : systemd-libs-219-73.0.3.el7_8.9.x86_64 23/28 Installing : 1:dbus-libs-1.10.24-14.0.1.el7_8.x86_64 24/28 Installing : systemd-219-73.0.3.el7_8.9.x86_64 25/28 Failed to get D-Bus connection: Operation not permitted Installing : elfutils-default-yama-scope-0.176-4.el7.noarch 26/28 Installing : 1:dbus-1.10.24-14.0.1.el7_8.x86_64 27/28 Installing : iputils-20160308-10.el7.x86_64 28/28 Verifying : acl-2.2.51-15.el7.x86_64 1/28 Verifying : 1:pkgconfig-0.27.1-4.el7.x86_64 2/28 Verifying : 2:tar-1.26-35.el7.x86_64 3/28 Verifying : libsmartcols-2.23.2-63.0.1.el7.x86_64 4/28 Verifying : util-linux-2.23.2-63.0.1.el7.x86_64 5/28 Verifying : elfutils-default-yama-scope-0.176-4.el7.noarch 6/28 Verifying : systemd-219-73.0.3.el7_8.9.x86_64 7/28 Verifying : binutils-2.27-43.base.0.1.el7_8.1.x86_64 8/28 Verifying : procps-ng-3.3.10-27.el7.x86_64 9/28 Verifying : 1:dbus-1.10.24-14.0.1.el7_8.x86_64 10/28 Verifying : systemd-libs-219-73.0.3.el7_8.9.x86_64 11/28 Verifying : qrencode-libs-3.4.1-3.el7.x86_64 12/28 Verifying : 7:device-mapper-1.02.164-7.0.1.el7_8.2.x86_64 13/28 Verifying : json-c-0.11-4.el7_0.x86_64 14/28 Verifying : dracut-033-568.0.3.el7.x86_64 15/28 Verifying : cryptsetup-libs-2.0.3-6.el7.x86_64 16/28 Verifying : lz4-1.7.5-3.el7.x86_64 17/28 Verifying : iputils-20160308-10.el7.x86_64 18/28 Verifying : xz-5.2.2-1.el7.x86_64 19/28 Verifying : kmod-libs-20-28.0.3.el7.x86_64 20/28 Verifying : 7:device-mapper-libs-1.02.164-7.0.1.el7_8.2.x86_64 21/28 Verifying : kpartx-0.4.9-131.0.1.el7.x86_64 22/28 Verifying : elfutils-libs-0.176-4.el7.x86_64 23/28 Verifying : libuser-0.60-9.el7.x86_64 24/28 Verifying : kmod-20-28.0.3.el7.x86_64 25/28 Verifying : 1:hardlink-1.0-19.el7.x86_64 26/28 Verifying : 1:dbus-libs-1.10.24-14.0.1.el7_8.x86_64 27/28 Verifying : libutempter-1.1.6-4.el7.x86_64 28/28 Installed: iputils.x86_64 0:20160308-10.el7 Dependency Installed: acl.x86_64 0:2.2.51-15.el7 binutils.x86_64 0:2.27-43.base.0.1.el7_8.1 cryptsetup-libs.x86_64 0:2.0.3-6.el7 dbus.x86_64 1:1.10.24-14.0.1.el7_8 dbus-libs.x86_64 1:1.10.24-14.0.1.el7_8 device-mapper.x86_64 7:1.02.164-7.0.1.el7_8.2 device-mapper-libs.x86_64 7:1.02.164-7.0.1.el7_8.2 dracut.x86_64 0:033-568.0.3.el7 elfutils-default-yama-scope.noarch 0:0.176-4.el7 elfutils-libs.x86_64 0:0.176-4.el7 hardlink.x86_64 1:1.0-19.el7 json-c.x86_64 0:0.11-4.el7_0 kmod.x86_64 0:20-28.0.3.el7 kmod-libs.x86_64 0:20-28.0.3.el7 kpartx.x86_64 0:0.4.9-131.0.1.el7 libsmartcols.x86_64 0:2.23.2-63.0.1.el7 libuser.x86_64 0:0.60-9.el7 libutempter.x86_64 0:1.1.6-4.el7 lz4.x86_64 0:1.7.5-3.el7 pkgconfig.x86_64 1:0.27.1-4.el7 procps-ng.x86_64 0:3.3.10-27.el7 qrencode-libs.x86_64 0:3.4.1-3.el7 systemd.x86_64 0:219-73.0.3.el7_8.9 systemd-libs.x86_64 0:219-73.0.3.el7_8.9 tar.x86_64 2:1.26-35.el7 util-linux.x86_64 0:2.23.2-63.0.1.el7 xz.x86_64 0:5.2.2-1.el7 Complete! bash-4.2# yum install -y iputils telnet Loaded plugins: ovl Package iputils-20160308-10.el7.x86_64 already installed and latest version Resolving Dependencies --> Running transaction check ---> Package telnet.x86_64 1:0.17-65.el7_8 will be installed --> Finished Dependency Resolution Dependencies Resolved ==================================================================================================================================== Package Arch Version Repository Size ==================================================================================================================================== Installing: telnet x86_64 1:0.17-65.el7_8 ol7_latest 64 k Transaction Summary ==================================================================================================================================== Install 1 Package Total download size: 64 k Installed size: 113 k Downloading packages: telnet-0.17-65.el7_8.x86_64.rpm | 64 kB 00:00:00 Running transaction check Running transaction test Transaction test succeeded Running transaction Installing : 1:telnet-0.17-65.el7_8.x86_64 1/1 Verifying : 1:telnet-0.17-65.el7_8.x86_64 1/1 Installed: telnet.x86_64 1:0.17-65.el7_8 Complete! bash-4.2# bash-4.2# ping bob PING bob (172.21.0.3) 56(84) bytes of data. 64 bytes from bob.foo (172.21.0.3): icmp_seq=1 ttl=64 time=0.112 ms 64 bytes from bob.foo (172.21.0.3): icmp_seq=2 ttl=64 time=0.084 ms 64 bytes from bob.foo (172.21.0.3): icmp_seq=3 ttl=64 time=0.087 ms ^C --- bob ping statistics --- 3 packets transmitted, 3 received, 0% packet loss, time 2033ms rtt min/avg/max/mdev = 0.084/0.094/0.112/0.014 ms bash-4.2# bash-4.2# telnet bob 3308 Trying 172.21.0.3... telnet: connect to address 172.21.0.3: Connection refused bash-4.2# bash-4.2# telnet bob Trying 172.21.0.3... telnet: connect to address 172.21.0.3: Connection refused bash-4.2# bash-4.2# telnet bob:3308 telnet: bob:3308: Name or service not known bob:3308: Unknown host bash-4.2# bash-4.2# mysql mysql -h bob -P 3308 --protocol=tcp -u root -p Enter password: ERROR 2003 (HY000): Can't connect to MySQL server on 'bob' (111) bash-4.2# bash-4.2# telnet bob 3306 Trying 172.21.0.3... Connected to bob. Escape character is '^]'. CHost '172.21.0.2' is not allowed to connect to this MySQL serverConnection closed by foreign host. bash-4.2# bash-4.2# telnet bob 33060 Trying 172.21.0.3... Connected to bob. Escape character is '^]'. �^C Connection closed by foreign host. bash-4.2# bash-4.2# bash-4.2# mysql mysql -h bob -P 33060 --protocol=tcp -u root -p Enter password: ERROR 2007 (HY000): Protocol mismatch; server version = 11, client version = 10 bash-4.2#