core26: apt update fails due to armhf being added to the architectures list on arm64 platforms
Metadata
Current evaluation
core26 arm64 builds failed because craft-archives auto-added armhf, 404ing on archive.ubuntu.com. Root cause fixed in craft-archives#255 (commit b4767b8, v2.2.2); snapcraft pinned craft-archives>=2.2.2 via merged PR #6415.
Resolution: closed resolved
Reason: Fixed upstream in craft-archives PR #255 (commit b4767b8, released in 2.2.2), then snapcraft merged PR #6415 to bump craft-archives to 2.2.2, resolving the armhf auto-add on Ubuntu 25.10+ arm64.
Evaluated by: mr-cal-bot
No scores available.
Issue body
### Check existing issues
- [x] I've verified that this bug isn't described by any existing issues.
### Bug description
Building a core26 snap on an arm64 host running 26.04 can result in the behaviour shown in the logs when snapcraft tries to update the apt sources list.
This is due to `armhf` automatically being added as an architecture as per https://github.com/canonical/craft-archives/blob/1b6bf121b3756ef420e0e9991c1a69da278d8490/craft_archives/repo/apt_sources_manager.py#L46 and the recent move of the arm64 archives to archive.ubuntu.com (armhf packages were not added). Previously, both arm64 and armhf packages were available in one place on ports.ubuntu.com, but recent arm64 LXD images use the new URL.
### Steps to reproduce
Build a core26 arm64 snap in a clean LXD environment with a recent image.
### Environment
Running on an arm64 self-hosted GitHub runner using the `snapcore/action-build` action, which uses LXD to run the build.
### snapcraft.yaml
```yaml
```
### Log output
```shell
:: 2026-07-07 09:22:09.425 Reading sources from '/etc/apt/sources.list.d/ubuntu.sources'.
:: 2026-07-07 09:22:09.425 Updating field 'Architectures' to 'arm64 armhf'
:: 2026-07-07 09:22:09.425 Updating source 'http://archive.ubuntu.com/ubuntu/'.
:: 2026-07-07 09:22:09.425 Updating source 'http://security.ubuntu.com/ubuntu/'.
:: 2026-07-07 09:22:09.425 Writing updated sources to '/etc/apt/sources.list.d/ubuntu.sources'.
:: 2026-07-07 09:22:09.425 Writing updated sources to '/etc/apt/sources.list.d/ubuntu.sources'.
:: 2026-07-07 09:22:09.425 Adding repository architecture: arm64
:: 2026-07-07 09:22:09.431 Refreshing repositories
...
:: 2026-07-07 09:22:20.233 :: Reading package lists...
:: 2026-07-07 09:22:20.251 :: E: Failed to fetch http://security.ubuntu.com/ubuntu/dists/resolute-security/main/binary-armhf/Packages 404 Not Found [IP: 91.189.91.95 80]
:: 2026-07-07 09:22:20.251 :: E: Failed to fetch http://archive.ubuntu.com/ubuntu/dists/resolute/main/binary-armhf/Packages 404 Not Found [IP: 185.125.190.94 80]
:: 2026-07-07 09:22:20.251 :: E: Failed to fetch http://archive.ubuntu.com/ubuntu/dists/resolute-updates/main/binary-armhf/Packages 404 Not Found [IP: 185.125.190.94 80]
```
Evaluation history
| Date | Model | Scores | Action | Summary |
|---|---|---|---|---|
| ~deepseek/deepseek-pro-latest | — | closed resolved | core26 arm64 builds failed because craft-archives auto-added armhf, 404ing on archive.ubuntu.com. Root cause fixed in craft-archives#255 (commit b4767b8, v2.2.2); snapcraft pinned craft-archives>=2.2.2 via merged PR #6415. | |
| stealth/space-bunny-alpha |
Impact:
55
Quick Win:
35
Complexity:
25
Confidence:
88
Actionability:
85
|
close resolved | core26 arm64 builds fail because craft-archives auto-adds armhf, which 404s on archive.ubuntu.com. Root cause fixed upstream in craft-archives#255 and snapcraft now pins craft-archives>=2.2.2 via merged PR #6415, but the issue is still open. | |
| stealth/space-bunny-alpha |
Impact:
75
Quick Win:
36
Complexity:
38
Confidence:
92
Actionability:
78
|
keep open | core26 arm64 builds with package repositories add armhf, causing 404s on Ubuntu archive hosts. Upstream craft-archives fixed this, but Snapcraft still needs to consume the release. | |
| qwen3.6-35b-a3b-mtp-q6 |
Impact:
75
Quick Win:
45
Staleness:
45
Complexity:
40
Confidence:
85
Support Request:
15
|
keep open | core26 snap builds on arm64 fail because craft-archives adds armhf to architectures list, causing apt update to fail with 404 errors from archive.ubuntu.com | |
| qwen/qwen3.6-35b-a3b |
Staleness:
15
Complexity:
45
Confidence:
90
Support Request:
10
|
keep open | Bug where apt update fails on arm64 core26 snaps because armhf is incorrectly added to architectures, causing 404s. Triaged, upstream fix in craft-archives, workaround available, awaiting implementation. | |
| qwen3.6-35b-a3b-mtp-q6 |
Staleness:
5
Complexity:
45
Confidence:
85
Support Request:
10
|
needs triage | Bug in craft-archives where armhf is incorrectly added to apt architectures on arm64 platforms, causing apt update failures with 404 errors when building core26 snaps. Currently untriaged with no maintainer response. |
Update history
| Date | Change |
|---|---|
| closed |
Related work
-
Likely Fixed By:
canonical/craft-archives#255
(confidence 100%)
Upstream fix: no longer auto-adds armhf as a compatible architecture on Ubuntu 25.10+ arm64.
-
Likely Fixed By:
canonical/snapcraft#6415
(confidence 100%)
Snapcraft dependency bump to craft-archives 2.2.2, which carries the fix.
-
Caused By:
canonical/craft-archives#230
(confidence 100%)
Upstream issue tracking the armhf auto-add root cause.
Related issues
| Issue | Project | State | Summary | Similarity |
|---|---|---|---|---|
| #6415 build(deps): bump craft-archives to 2.2.2 | snapcraft | merged | Merged PR #6415 (mr-cal) bumped craft-archives 2.2.1 -> 2.2.2 in snapcraft's dependency pins, fixing #6326 where core26 arm64 builds failed because craft-archives auto-added armhf to the apt architectures list. | |
| #230 Don't add armhf as a compatible architecture for 25.10 and newer | craft-archives | closed | Fixed by merged PR #255 (commit b4767b8), released in craft-archives 2.2.2: on Ubuntu 25.10+ arm64 hosts no longer auto-add armhf to ubuntu.sources, since arm64 moved to archive.ubuntu.com. | |
| #2018609 Can't update repositories when building for different arch from host | snapcraft (launchpad) | closed | Cross-arch apt sources picked archive.ubuntu.com instead of ports.ubuntu.com; fixed on the snapcraft side by canonical/craft-archives#96 and snapcore/snapcraft#4303 (commit 1db0f39), released in 7.5.1/7.5.2; reporter confirmed resolved. |