Can you brick your device installing snapshot packages?

Installing and Using OpenWrt
1

As title says.

Ever since I bricked my previous TP Link RE450, just want to be careful about this stuff.

I want to install the following package which is a snapshot build: Travelmate

Are there any risks?

2

There are always risks, regardless of release builds (no one can test each and every one of the >700 supported devices supported by LEDE, active LEDE contributors only only a fraction of those to begin with) or snapshot builds. Due to their very nature (rebuilt roughly daily), snapshot builds have seen considerably less (read none, you are the guinea pig) testing (especially when it comes to device specific topics) than release builds.

That does however not mean snapshot builds would be by definition unstable, but you should have a fallback handy (it's always good if your device supports a robust recovery method); the same is also very useful for release builds as well.

3

Hi,

Thanks but in this case the LEDE build installed on the device is a stable one, only the package is a snapshot.

Can a snapshot package cause a device with a stable LEDE build to brick itself?

4

@openwrt_newbie999

Travelmate has been developed on a TP Link RE450 (see above linked support thread)... there is a good chance that it works ootb ... :wink:

5

Yes, that's not even unlikely if you try to mix a stable firmware with unstable packages (libraries in particular) or older snapshots with current/ updated packages (or the reverse), due to ABI mismatches; firstboot should help in those cases though.

6

@dibdot
Thanks. Going to install it, but better safe than sorry. Is it a snapshot then because its not been tested on other devices?

@slh
Thanks for the info :slight_smile:

7

Sounds like you have not yet understood the basic terminology in use.

  • "release" refers to official releases like 17.01.4 made from a "stable" git branch, and the travelmate package is available also for that. You can install travelmate quite normally to a 17.01.X release.
  • "snapshot" usually refers to the daily development build made from the git "master" branch by an automatic buildbot. That may contain experimental features and although it is usually rather ok, there may be some problem every now and then.

Packages are available separately for both releases and snapshots. Releases usually contain older "known to be ok" versions of packages, while snapshot packages get updated more often.

Neither release nor snapshot packages are tested for all devices. There are hundreds of supported devices and thousands of packages, so testing all packages for all devices separate devices would be impossible.

8

Thanks for the explanation. I understand what they refer to as far as the firmware is concerned.

I thought that the same applies to packages as well, because for example Travelmate is available for down at URL: https://downloads.lede-project.org/snapshots/packages/x86_64/packages/
And then you also have packages that are available at URL: https://downloads.lede-project.org/releases/packages-17.01/

So intuitively that means that even packages have release builds and snapshot builds. And that snapshot packages might not completely be stable (possibly bricking your device).

9

Yes.
Releases and snapshot builds are fully separate. They may even have different compilation libraries etc., so that the binaries can be totally incompatible.

You should always use matching packages. Release packages for that release's firmware, and today's snapshot package's for today's snapshot firmware.

(Snapshots get constantly re-compiled, so it is possible that a snapshot package compiled today does not work with a snapshot firmware compiled two weeks ago. That incompatibility does not happen often, but may happen...)

Ps.
your opkg package manager has been configured so that if offers downloads from the correct download repo (release packages for release firmware, etc.). So, just use opkg to install packages and you are usually fine.

10

@hnyman

All starting to make sense now.

One piece of the puzzle that I don't quite get then. You said you should only install release packages on release firmware and snapshot packages on snapshot firmware.

However if you check out the Travelmate Package Documentation which is for a package that happens to live in the snapshot package directory, it says:

Prerequisites:
LEDE 17.01 or latest snapshot
iwinfo for wlan scanning

This implies that a snapshot package is available on both LEDE 17.01+ release firmware and the latest LEDE snapshot build, which kind of contradicts what we discussed above.

11

Travelmate is implemented entirely in shell script, thus it doesn't depend on any low-level features of the OS. It should work on any version.

12

I see.

So that would mean that some snapshot packages can be installed on release builds and that simply installing through opkg does not necessarily mean its completely safe.