It is very common that Linux server seems to hang when starting services such as Sendmail/Postfix or httpd.
The main cause for this is failure to resolve hostname i.e. Linux cannot look up the name of the machine/server via DNS lookup. Your server will boot but it will take some time and service may not work perfectly.
First, make sure the file /etc/resolv.conf has the correct values for your machine’s DNS (NS1 and NS2) server ip address:
$ cat /etc/resolv.conf
Output:
nameserver 202.54.1.20 nameserver 202.54.1.22
If you are not sure about correct nameserver IP then ask your network/sys administrator for correct IPs.
Another solution is to add your hostname to /etc/hosts file, which is the static table lookup for host names.
$ cat /etc/hosts
Output:
127.0.0.1 localhost.localdomain localhost 192.168.1.21 www.cyberciti.biz portal 192.168.1.254 router.cyberciti.biz router 192.168.1.25 laptop.cyberciti.biz lappy
Above method is quite useful if you are using Linux on a network without a DNS server. If you are going to configure 192.168.1.21 as the DNS server then you need to add your hostname to /etc/hosts file.
🐧 Get the latest tutorials on Linux, Open Source & DevOps via:
- RSS feed or Weekly email newsletter
- Share on Twitter • Facebook • 0 comments... add one ↓
| Category | List of Unix and Linux commands |
|---|---|
| File Management | cat |
| Firewall | Alpine Awall • CentOS 8 • OpenSUSE • RHEL 8 • Ubuntu 16.04 • Ubuntu 18.04 • Ubuntu 20.04 |
| Network Utilities | dig • host • ip • nmap |
| OpenVPN | CentOS 7 • CentOS 8 • Debian 10 • Debian 8/9 • Ubuntu 18.04 • Ubuntu 20.04 |
| Package Manager | apk • apt |
| Processes Management | bg • chroot • cron • disown • fg • jobs • killall • kill • pidof • pstree • pwdx • time |
| Searching | grep • whereis • which |
| User Information | groups • id • lastcomm • last • lid/libuser-lid • logname • members • users • whoami • who • w |
| WireGuard VPN | Alpine • CentOS 8 • Debian 10 • Firewall • Ubuntu 20.04 |
