Ubuntu apt fails with Temporary Failure Resolving archive.ubuntu.com although the link is up. This is a narrower problem than a complete Linux failure: the most useful evidence is the condition under which it begins.
Start with the evidence
Primary symptom. Ubuntu apt fails with Temporary Failure Resolving archive.ubuntu.com although the link is up. Record the precise point of failure and whether the same input, account or connected device succeeds in another supported mode. That working comparison establishes the scope of the repair.
Where this failure originates
The first hypothesis is a mismatch in the failing path. Check name resolution separately from reachability to a known trusted IP. The second is a lower-level state that the interface may not show: inspect resolvectl status, DHCP DNS options and split-DNS routes before editing system files. A third possibility is a feature or version limitation, which should be checked against supported documentation before a reset.
For this Linux issue, capture journal timestamps, service unit, kernel version and mandatory access control policy and compare the same service on a non-production machine with matching configuration. Preserve the last known working configuration so you can tell whether a successful retry came from an actual correction or a temporary recovery.
Pick the right branch
| What you observe | What it suggests | Focused response |
|---|---|---|
| Ubuntu apt fails with Temporary Failure Resolving archive.ubuntu.com although the link is up | The failure affects the specific workflow described here; the entire system is not necessarily broken. | Check name resolution separately from reachability to a known trusted IP. |
| The basic comparison exposes a difference between a working and failing configuration. | A local setting, version, account context or device route deserves attention. | Restore the authorized DNS resolver or correct a broken netplan/systemd-resolved configuration. |
| The same failure persists after a reversible correction. | A deeper dependency or compatibility issue may remain. | Inspect resolvectl status, DHCP DNS options and split-DNS routes before editing system files. |
Before changing anything: Back up configuration and verify authorization before applying changes; do not disable access controls on production services. Save a screenshot or anonymized log line, record the previous setting, and back up relevant user data. Do not reset every related service just because one test fails.
Choose a recovery route. The Beginner path checks check name resolution separately from reachability to a known trusted IP. The Advanced path investigates inspect resolvectl status, DHCP DNS options and split-DNS routes before editing system files. They address different evidence; use the path that matches your result.
Step-by-Step Troubleshooting
Choose the Beginner route for reversible checks or Advanced for evidence-driven diagnosis.
Identify the exact failure boundary
Ubuntu apt fails with Temporary Failure Resolving archive.ubuntu.com although the link is up. Before editing settings, note the exact time, affected account or device, and whether it started after an update, move, hardware change or network change. This is the baseline for the Ubuntu Temporary Failure Resolving archive.ubuntu.com: Test DNS Safely guide.
Check name resolution separately from reachability to a known
Check name resolution separately from reachability to a known trusted IP. Observe whether the symptom changes. A clean comparison tells you which part of the process is healthy and avoids unnecessary resets.
Adjust the authorized DNS resolver or correct a broken
Restore the authorized DNS resolver or correct a broken netplan/systemd-resolved configuration. Change only this variable, record its former value, and try the failing action once. If there is no improvement, restore the prior configuration before exploring the Advanced route.
Verify apt update resolves the intended official mirror and lists
apt update resolves the intended official mirror and lists repository metadata. Repeat using the same account, network, file, title or hardware condition that previously failed. Do not count a different test as confirmation.
Extract technical context
Collect the error text or state relevant to Ubuntu Temporary Failure Resolving archive.ubuntu.com: Test DNS Safely. Record journal timestamps, service unit, kernel version and mandatory access control policy; anonymize account IDs, public IPs and secret-bearing log fragments before sharing.
Inspect resolvectl status, DHCP DNS options and split-DNS routes
Inspect resolvectl status, DHCP DNS options and split-DNS routes before editing system files. Record the difference between successful and failed cases and keep the first meaningful error rather than the last cascade message.
resolvectl statusSeparate two competing explanations
Where practical, compare the same service on a non-production machine with matching configuration. If the alternate case works, return to the single configuration difference instead of changing multiple services. Use the vendor-supported method for your current version.
Confirm integrity after repair
apt update resolves the intended official mirror and lists repository metadata. Leave the previous value documented for rollback, then monitor one normal operating cycle. If symptoms recur, attach the sanitized evidence to a vendor or administrator support request.
After your guided checks
After the first corrective action, interpret the result carefully. If the original task now works, leave the other settings unchanged. If it still fails, inspect resolvectl status, DHCP DNS options and split-DNS routes before editing system files. Compare the same service on a non-production machine with matching configuration rather than adding random fixes on top of one another.
For escalation, retain journal timestamps, service unit, kernel version and mandatory access control policy, the original output, and a single before/after comparison. Redact passwords, tokens and personal data. A support agent can then distinguish the same service on a non-production machine with matching configuration from a general outage without repeating risky actions.
Optional targeted diagnostic
Inspect per-link resolver configuration; this does not edit networking. Commands below are illustrative and must be run only on systems you are authorized to inspect.
resolvectl statusAcceptance test
Pass condition: apt update resolves the intended official mirror and lists repository metadata. The validation must exercise the same path that failed originally. A successful settings screen, single ping, application homepage or idle system is not enough if the original failure appears during a different action.
Repeat the test under the original conditions once after a safe relaunch, reconnect or new session. For intermittent failures, record the time and the difference between a clean result and a failed one instead of claiming success from a single attempt.
When to escalate
If the problem persists, restore any test-only settings, preserve the evidence and stop before destructive reset, firmware flash or credential recreation. Give official support the exact symptom, the first failing timestamp and what the comparison established. Back up configuration and verify authorization before applying changes; do not disable access controls on production services.
Prevent recurrence: Document the working correction: Restore the authorized DNS resolver or correct a broken netplan/systemd-resolved configuration. Retain the accepted result (apt update resolves the intended official mirror and lists repository metadata) as a future regression test after configuration, software or hardware changes.
Solution Checklist
Questions specific to this fault
How do I know the symptom is actually resolved?
apt update resolves the intended official mirror and lists repository metadata. A generic diagnostic test outside the affected workflow is not a substitute.
Should I reset or reinstall everything first?
No. Check name resolution separately from reachability to a known trusted IP. Then choose the smallest supported intervention: restore the authorized DNS resolver or correct a broken netplan/systemd-resolved configuration. Preserve recoverable settings and user data.
What should I include in a support request?
Provide the exact failing action, product and version, time, non-sensitive log evidence, and this deeper observation: Inspect resolvectl status, DHCP DNS options and split-DNS routes before editing system files. Do not include credentials or private customer data.