getent hosts

Programs such as curl and ssh do not use dig: they ask the system resolver, which reads /etc/hosts first and then the DNS servers in /etc/resolv.conf (nameserver lines, tried in order). getent hosts NAME shows exactly what a program would get. When curl and dig disagree, one of these two files is why.

getent hosts command usage

getent hosts NAME
cat /etc/resolv.conf
cat /etc/hosts

getent hosts examples

getent hosts webServer.lab

Resolves webServer.lab the way programs do, hosts file included.

cat /etc/resolv.conf

Shows which DNS servers this device asks, and its search domains.

cat /etc/hosts

Shows names pinned to addresses on this device, which win over DNS.

echo 'nameserver 10.0.1.2' > /etc/resolv.conf

Makes 10.0.1.2 this device's only DNS server.

Reading the output

$ cat /etc/resolv.conf; getent hosts webServer.lab
nameserver 10.0.1.2
10.0.2.10        webServer.lab  webServer.lab

• nameserver 10.0.1.2: every lookup goes to this address first. If nothing answers DNS there, every name fails.
• getent printed an address: programs can resolve it. Nothing printed (exit 2): they cannot.

Pitfalls

• A stale line in /etc/hosts silently wins over a correct DNS answer.

Run it on real machines