# PING command in a Docker container (Ubuntu)

apt-get update
apt-get install iputils-ping

# ping 172.17.0.2
/bin/sh: 1: ping: not found
# apt-get update
Get:1 http://deb.debian.org/debian bullseye InRelease [116 kB]
Get:2 http://deb.debian.org/debian-security bullseye-security InRelease [48.4 kB]
Get:3 http://deb.debian.org/debian bullseye-updates InRelease [44.1 kB]
Get:4 http://deb.debian.org/debian bullseye/main amd64 Packages [8183 kB]
Get:5 http://deb.debian.org/debian-security bullseye-security/main amd64 Packages [216 kB]
Get:6 http://deb.debian.org/debian bullseye-updates/main amd64 Packages [14.6 kB]
Fetched 8622 kB in 2s (3682 kB/s)                         
Reading package lists... Done
# apt-get install iputils-ping
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
The following additional packages will be installed:
libcap2 libcap2-bin libpam-cap
The following NEW packages will be installed:
iputils-ping libcap2 libcap2-bin libpam-cap
0 upgraded, 4 newly installed, 0 to remove and 1 not upgraded.
Need to get 121 kB of archives.
After this operation, 348 kB of additional disk space will be used.
Do you want to continue? [Y/n] y
Get:1 http://deb.debian.org/debian bullseye/main amd64 libcap2 amd64 1:2.44-1 [23.6 kB]
Get:2 http://deb.debian.org/debian bullseye/main amd64 libcap2-bin amd64 1:2.44-1 [32.6 kB]
Get:3 http://deb.debian.org/debian bullseye/main amd64 iputils-ping amd64 3:20210202-1 [49.8 kB]
Get:4 http://deb.debian.org/debian bullseye/main amd64 libpam-cap amd64 1:2.44-1 [15.4 kB]
Fetched 121 kB in 0s (426 kB/s)    
debconf: delaying package configuration, since apt-utils is not installed
Selecting previously unselected package libcap2:amd64.
(Reading database ... 7140 files and directories currently installed.)
Preparing to unpack .../libcap2_1%3a2.44-1_amd64.deb ...
Unpacking libcap2:amd64 (1:2.44-1) ...
Selecting previously unselected package libcap2-bin.
Preparing to unpack .../libcap2-bin_1%3a2.44-1_amd64.deb ...
Unpacking libcap2-bin (1:2.44-1) ...
Selecting previously unselected package iputils-ping.
Preparing to unpack .../iputils-ping_3%3a20210202-1_amd64.deb ...
Unpacking iputils-ping (3:20210202-1) ...
Selecting previously unselected package libpam-cap:amd64.
Preparing to unpack .../libpam-cap_1%3a2.44-1_amd64.deb ...
Unpacking libpam-cap:amd64 (1:2.44-1) ...
Setting up libcap2:amd64 (1:2.44-1) ...
Setting up libcap2-bin (1:2.44-1) ...
Setting up libpam-cap:amd64 (1:2.44-1) ...
debconf: unable to initialize frontend: Dialog
debconf: (No usable dialog-like program is installed, so the dialog based frontend cannot be used. at /usr/share/perl5/Debconf/FrontEnd/Dialog.pm line 78.)
debconf: falling back to frontend: Readline
debconf: unable to initialize frontend: Readline
debconf: (Can't locate Term/ReadLine.pm in @INC (you may need to install the Term::ReadLine module) (@INC contains: /etc/perl /usr/local/lib/x86_64-linux-gnu/perl/5.32.1 /usr/local/share/perl/5.32.1 /usr/lib/x86_64-linux-gnu/perl5/5.32 /usr/share/perl5 /usr/lib/x86_64-linux-gnu/perl-base /usr/lib/x86_64-linux-gnu/perl/5.32 /usr/share/perl/5.32 /usr/local/lib/site_perl) at /usr/share/perl5/Debconf/FrontEnd/Readline.pm line 7.)
debconf: falling back to frontend: Teletype
Setting up iputils-ping (3:20210202-1) ...
Processing triggers for libc-bin (2.31-13+deb11u5) ...
# ping 172.17.0.2
PING 172.17.0.2 (172.17.0.2) 56(84) bytes of data.
64 bytes from 172.17.0.2: icmp_seq=1 ttl=64 time=0.034 ms
64 bytes from 172.17.0.2: icmp_seq=2 ttl=64 time=0.016 ms
64 bytes from 172.17.0.2: icmp_seq=3 ttl=64 time=0.035 ms
64 bytes from 172.17.0.2: icmp_seq=4 ttl=64 time=0.017 ms
64 bytes from 172.17.0.2: icmp_seq=5 ttl=64 time=0.035 ms
^C
--- 172.17.0.2 ping statistics ---
5 packets transmitted, 5 received, 0% packet loss, time 4122ms
rtt min/avg/max/mdev = 0.016/0.027/0.035/0.008 ms
#