> ## Documentation Index > Fetch the complete documentation index at: https://help.freakhosting.com/llms.txt > Use this file to discover all available pages before exploring further. # How to Fix "Temporary Failure in Name Resolution" on Linux > Fix "Temporary failure in name resolution" on Linux: check the network, set working DNS servers, restart systemd-resolved and add your hostname to /etc/hosts. "Temporary failure in name resolution" means Linux couldn't turn a name such as `example.com` into an IP address. Either the server has no working network, no working DNS resolver is configured, the local resolver (systemd-resolved on Ubuntu) is stopped, or a firewall blocks DNS. Test with `ping -c 3 1.1.1.1` and `resolvectl status`, then set working DNS servers in your network configuration. ```text theme={null} ping: example.com: Temporary failure in name resolution Temporary failure resolving 'archive.ubuntu.com' curl: (6) Could not resolve host: example.com sudo: unable to resolve host web01: Temporary failure in name resolution ``` | Difficulty | Time | Works on | Needs | | - | - | - | - | | Beginner | 5 to 15 minutes | Ubuntu 22.04 / 24.04, Debian 12 / 13, AlmaLinux and Rocky Linux 9 / 10 | Root or sudo access | ## Before you start * A **DNS resolver** is the server that answers "which IP belongs to this name?". Your server asks the resolvers in its network settings. * If the message starts with `sudo: unable to resolve host`, jump to Cause 4 below: only your server's own name is missing. * If SSH stopped working too, use the [VNC console](https://help.freakhosting.com/portals/vps-panel/how-to-enable-and-use-vnc-console-access.md). * Commands use `sudo`. As root, leave it out. ## Step 1: Is it DNS or the whole network? ```bash theme={null} ping -c 3 1.1.1.1 ping -c 3 example.com ``` | Result | Meaning | | - | - | | IP works, name fails | DNS problem: Causes 1 to 3 | | Both fail | No network at all: see [SSH connection timed out, Cause 4](https://help.freakhosting.com/portals/other/how-to-fix-ssh-connection-timed-out.md) | ## Cause 1: No working DNS servers configured An edit to Netplan, NetworkManager or `/etc/resolv.conf` can leave the server with no resolvers, or with ones that no longer answer. **Check:** > [tab] Ubuntu (systemd-resolved) > > ```bash theme={null} > resolvectl status > ``` > > Each network interface should show `DNS Servers:` with at least one address. `/etc/resolv.conf` shows `nameserver 127.0.0.53`: that is the local resolver, which forwards to those servers. That line is correct; don't replace it. > [tab] Debian / AlmaLinux / Rocky > > ```bash theme={null} > cat /etc/resolv.conf > ``` > > You need at least one `nameserver` line with a reachable resolver. **Fix:** set resolvers where your network tool stores them, for example `1.1.1.1` and `9.9.9.9`. On Ubuntu that is the `nameservers` block in Netplan, on AlmaLinux and Rocky it is NetworkManager. Step-by-step instructions for each system are in [change DNS resolvers on Linux](https://help.freakhosting.com/portals/other/how-to-change-dns-resolvers-on-linux.md). The [VPS Panel DNS resolver setting](https://help.freakhosting.com/portals/vps-panel/how-to-change-ipv4-public-dns-resolvers.md) only takes effect if your server uses the panel's network configuration. ## Cause 2: systemd-resolved is stopped (Ubuntu) If `/etc/resolv.conf` points to `127.0.0.53` but the service behind it doesn't run, every lookup fails. **Check:** ```bash theme={null} systemctl status systemd-resolved ``` **Fix:** ```bash theme={null} sudo systemctl enable --now systemd-resolved ``` If you replaced `/etc/resolv.conf` with your own file and then stopped the service, either keep your file and leave the service off, or restore the link: ```bash theme={null} sudo ln -sf /run/systemd/resolve/stub-resolv.conf /etc/resolv.conf ``` ## Cause 3: A firewall blocks outgoing DNS DNS uses port `53` over UDP and TCP. If you set your firewall to deny outgoing traffic, lookups fail. **Check:** > [tab] Ubuntu / Debian (UFW) > > ```bash theme={null} > sudo ufw status verbose > ``` > > `Default: deny (incoming), allow (outgoing)` is normal. `deny (outgoing)` needs an exception for DNS. > [tab] AlmaLinux / Rocky (firewalld) > > firewalld zones filter incoming traffic, so outgoing DNS works unless you added outbound policies or rules. List everything that is loaded with `sudo nft list ruleset`. **Fix** (UFW with outgoing denied): ```bash theme={null} sudo ufw allow out 53 ``` ## Cause 4: Your own hostname isn't in /etc/hosts After you [change the hostname](https://help.freakhosting.com/portals/other/how-to-change-the-hostname-on-linux.md), `sudo` prints `unable to resolve host` before it runs your command. Only the server's own name is missing. **Check:** ```bash theme={null} hostname cat /etc/hosts ``` **Fix:** add the hostname to `/etc/hosts`. On Ubuntu and Debian, use `127.0.1.1`: ```text theme={null} 127.0.0.1 localhost 127.0.1.1 web01 ``` Replace `web01` with the output of `hostname`. The change works immediately. ## How to check it worked ```bash theme={null} getent hosts example.com ``` An IP address followed by the name means lookups work. On Ubuntu, `resolvectl query example.com` also shows which server answered. ## Frequently asked questions ### Why is it called "temporary" if it never fixes itself? It is the standard text for the `EAI_AGAIN` error, which the resolver library returns when no DNS server gave an answer and a retry might work. It doesn't mean the problem will go away on its own. ### Can I just edit /etc/resolv.conf? On Ubuntu, systemd-resolved or Netplan overwrites it. On AlmaLinux and Rocky, NetworkManager does. Make the change in the tool that owns the file, as in Cause 1. ### Apt says "Temporary failure resolving". Is the mirror down? Usually not. That message comes from your server's DNS, not the mirror. Fix DNS first, then see [apt and dnf repository errors](https://help.freakhosting.com/portals/other/how-to-fix-apt-and-dnf-repository-errors.md) if `apt update` still fails. ## Related guides > [card] [VPS and dedicated server guides](https://help.freakhosting.com/portals/other/vps-and-dedicated-server-guides.md) > > Every guide in this section. > [card] [Change DNS resolvers](https://help.freakhosting.com/portals/other/how-to-change-dns-resolvers-on-linux.md) > > Set resolvers on every distribution. > [card] [Static IP with Netplan](https://help.freakhosting.com/portals/other/how-to-configure-a-static-ip-with-netplan.md) > > Fix a broken Ubuntu network config. > [card] [Change the hostname](https://help.freakhosting.com/portals/other/how-to-change-the-hostname-on-linux.md) > > Rename the server and update /etc/hosts. > [card] [apt and dnf repository errors](https://help.freakhosting.com/portals/other/how-to-fix-apt-and-dnf-repository-errors.md) > > When package updates fail. *** > [!NOTE] > > **Checked against the official systemd [resolvectl](https://www.freedesktop.org/software/systemd/man/latest/resolvectl.html) and [systemd-resolved](https://www.freedesktop.org/software/systemd/man/latest/systemd-resolved.service.html) manuals and the [Ubuntu Server networking guide](https://ubuntu.com/server/docs/explanation/networking/configuring-networks/)** on 4 November 2026; the `ping`, `curl`, `apt` and `sudo` errors and the `/etc/hosts` fix were reproduced with an empty resolver configuration on Ubuntu 24.04 LTS. Service restarts and the firewalld check were not tested. > [!NOTE] > > ### Need Extra Help? > > If you encounter any issues, our support team is ready to assist: > > * **Live Chat:** Quick assistance via our website. > * **Support Ticket:** [Open a Ticket](https://freakhosting.com/clientarea/submitticket.php) > * **Discord:** [Join our Community](https://discord.gg/freakhosting) > * **Email:** [support@freakhosting.com](mailto:support@freakhosting.com) > [!TIP] > > ### Save on Your Hosting > > Ready to upgrade your hosting? Use code **KB20** at checkout for **20% off** your first order! *** **Last Updated:** November 2026 This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.