# Can't start Slicer on Linux on one machine

**URL:** <https://discourse.slicer.org/t/cant-start-slicer-on-linux-on-one-machine/8175>\
**Category:** Support\
**Created:** [August 26, 2019, 7:12am UTC](https://discourse.slicer.org/t/cant-start-slicer-on-linux-on-one-machine/8175 "2019-08-26T07:12:06Z")\
**Posts on this page:** 18\
**Page:** 3

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**Author:** ![chir.set](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/chir.set/32/66982_2.png) [@chir.set](https://discourse.slicer.org/u/chir.set)\
**Post date:** [October 31, 2019, 12:44pm UTC](https://discourse.slicer.org/t/cant-start-slicer-on-linux-on-one-machine/8175/41 "2019-10-31T12:44:22Z")

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> [@Leon](#):
>
> then run the executable ‘slicer’.  
> That’s it!

You have probably not used it long enough to say ‘Ooops! what’s happening ? Where is Slicer ?’. That happened twice to me, building it was the only way in these situations.

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**Author:** ![lassoan](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/lassoan/32/13_2.png) [@lassoan](https://discourse.slicer.org/u/lassoan)\
**Post date:** [October 31, 2019, 12:54pm UTC](https://discourse.slicer.org/t/cant-start-slicer-on-linux-on-one-machine/8175/42 "2019-10-31T12:54:55Z")

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It is quite likely that the same Slicer binaries don’t work correctly on all Linux flavours and configurations, but I guess most Linux users chose the platform because they prefer to have more control over their systems and got used to building components on their own.

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**Author:** ![pieper](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/pieper/32/8_2.png) [@pieper](https://discourse.slicer.org/u/pieper)\
**Post date:** [October 31, 2019, 1:54pm UTC](https://discourse.slicer.org/t/cant-start-slicer-on-linux-on-one-machine/8175/43 "2019-10-31T13:54:12Z")

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Yes, and those same Linux systems tend to have variability in compiler versions and directory layouts, so some build issues can be expected from time to time. It’s actually kind of remarkable that some much works well most of the time.

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**Author:** ![Leon](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/leon/32/1468_2.png) [@Leon](https://discourse.slicer.org/u/Leon)\
**Post date:** [October 31, 2019, 1:57pm UTC](https://discourse.slicer.org/t/cant-start-slicer-on-linux-on-one-machine/8175/44 "2019-10-31T13:57:35Z")

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Ever thought about distributing Slicer as a Flatpak? 😉  
[https://flatpak.org/](https://flatpak.org/)

Other software packages also use this (check it out for yourself).

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**Author:** ![gaoyi.cn](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/gaoyi.cn/32/1422_2.png) [@gaoyi.cn](https://discourse.slicer.org/u/gaoyi.cn)\
**Post date:** [October 31, 2019, 2:40pm UTC](https://discourse.slicer.org/t/cant-start-slicer-on-linux-on-one-machine/8175/45 "2019-10-31T14:40:37Z")

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coz i’m developing based on Slicer. that needs building from source.

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**Author:** ![pieper](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/pieper/32/8_2.png) [@pieper](https://discourse.slicer.org/u/pieper)\
**Post date:** [October 31, 2019, 6:07pm UTC](https://discourse.slicer.org/t/cant-start-slicer-on-linux-on-one-machine/8175/46 "2019-10-31T18:07:53Z")

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> [@Leon](#):
>
> Ever thought about distributing Slicer as a Flatpak?

Yes, and there’s also [https://snapcraft.io/](https://snapcraft.io/). Could be handy if anyone wants to take it on.

But realistically it hasn’t come up that often - the linux binaries we build seem to be pretty compatible with the distributions I use anyway.

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**Author:** ![gaoyi.cn](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/gaoyi.cn/32/1422_2.png) [@gaoyi.cn](https://discourse.slicer.org/u/gaoyi.cn)\
**Post date:** [November 2, 2019, 2:19am UTC](https://discourse.slicer.org/t/cant-start-slicer-on-linux-on-one-machine/8175/47 "2019-11-02T02:19:32Z")

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by usnig strace SlicerApp-real, it seems that slicer is searching for libssl.so.1.1 in many places, with no luck.

However, in the entire superbuilld dir, i found ssl lib in:  
./OpenSSL/libssl.so.1.0.0

Also in cmake, the default ssl version is 1.0.2n

I’m trying to see where in the process the 1.1 is requested…

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**Author:** ![gaoyi.cn](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/gaoyi.cn/32/1422_2.png) [@gaoyi.cn](https://discourse.slicer.org/u/gaoyi.cn)\
**Post date:** [November 2, 2019, 6:56am UTC](https://discourse.slicer.org/t/cant-start-slicer-on-linux-on-one-machine/8175/48 "2019-11-02T06:56:56Z")

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Hi Steve, Hi Andras, @pieper @lassoan

I believed the problem on my machine was that python needs openssl 1.1.0 and up. I then upgraded openssl super build version to 1.1.1d. It then requires curl to be upgraded to 7.66, which I did, and it worked.

I believe this may be related with several recent issues:

- [Building Slicer on a freshly installed Ubuntu 18.04](https://discourse.slicer.org/t/building-slicer-on-a-freshly-installed-ubuntu-18-04/5627/10)  
Initially I though this solves the problem (using both system ssl and curl). But though Slicer built, it doesn’t work properly: numpy can’t be imported.
- [https://issues.slicer.org/view.php?id=4617](https://issues.slicer.org/view.php?id=4617)
- [Slicer crash on fresh build](https://discourse.slicer.org/t/slicer-crash-on-fresh-build/351)  
I had the same problem. I though it was a python problem. But latter found the problem is ssl

Now I have a freshly built Slicer…

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<div class="post-metadata">

**Author:** ![lassoan](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/lassoan/32/13_2.png) [@lassoan](https://discourse.slicer.org/u/lassoan)\
**Post date:** [November 3, 2019, 2:11am UTC](https://discourse.slicer.org/t/cant-start-slicer-on-linux-on-one-machine/8175/49 "2019-11-03T02:11:19Z")

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It is great that you were able to figure out all these and thank you very much for sharing the results.

@jcfr @Sam_Horvath Can you make the necessary changes in Slicer’s build system?

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<div class="post-metadata">

**Author:** ![pieper](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/pieper/32/8_2.png) [@pieper](https://discourse.slicer.org/u/pieper)\
**Post date:** [November 3, 2019, 6:13pm UTC](https://discourse.slicer.org/t/cant-start-slicer-on-linux-on-one-machine/8175/50 "2019-11-03T18:13:21Z")

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@gaoyi.cn Yes, nice work Yi! Is there a chance you could make a pull request with the needed changes?

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<div class="post-metadata">

**Author:** ![pieper](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/pieper/32/8_2.png) [@pieper](https://discourse.slicer.org/u/pieper)\
**Post date:** [November 3, 2019, 6:20pm UTC](https://discourse.slicer.org/t/cant-start-slicer-on-linux-on-one-machine/8175/51 "2019-11-03T18:20:15Z")

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Oops, I see you already made a PR [https://github.com/Slicer/Slicer/pull/1245/files](https://github.com/Slicer/Slicer/pull/1245/files)

@gaoyi.cn are these the right fixes? I’m curious why you closed it.

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<div class="post-metadata">

**Author:** ![gaoyi.cn](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/gaoyi.cn/32/1422_2.png) [@gaoyi.cn](https://discourse.slicer.org/u/gaoyi.cn)\
**Post date:** [November 14, 2019, 11:12am UTC](https://discourse.slicer.org/t/cant-start-slicer-on-linux-on-one-machine/8175/53 "2019-11-14T11:12:36Z")

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Hi Steve,

I recently did many test builds on different machines under different internet connection conditions. I believe the proposed changes does solve my problem. So I put them together and create a new pull request. Please advice.

Thanks!  
yi

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<div class="post-metadata">

**Author:** ![pieper](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/pieper/32/8_2.png) [@pieper](https://discourse.slicer.org/u/pieper)\
**Post date:** [November 19, 2019, 9:10pm UTC](https://discourse.slicer.org/t/cant-start-slicer-on-linux-on-one-machine/8175/54 "2019-11-19T21:10:50Z")

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Hi Yi -

Were you doing a debug build or a release build? For me (debug build on mac), with the new curl the library had an extra `-d` in the filename and I could only link if I renamed the file.

See: [https://github.com/Slicer/Slicer/pull/1260](https://github.com/Slicer/Slicer/pull/1260)

-Steve

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<div class="post-metadata">

**Author:** ![gaoyi.cn](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/gaoyi.cn/32/1422_2.png) [@gaoyi.cn](https://discourse.slicer.org/u/gaoyi.cn)\
**Post date:** [November 20, 2019, 8:50am UTC](https://discourse.slicer.org/t/cant-start-slicer-on-linux-on-one-machine/8175/55 "2019-11-20T08:50:37Z")

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HI Steve,

I did release build before. Let me try a Debug build on linux.

Previously, the configuration for building a static curl was by " -DCURL\_STATICLIB:BOOL=ON" in the SuperBuild/External\_curl.cmake file.

After changing to the newer version, this flag was not recognized. Changing to  
-DBUILD\_SHARED\_LIBS:BOOL=OFF  
solved my problem in release build on LInux.

Let me try debug and report back.

yi

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<div class="post-metadata">

**Author:** ![gaoyi.cn](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/gaoyi.cn/32/1422_2.png) [@gaoyi.cn](https://discourse.slicer.org/u/gaoyi.cn)\
**Post date:** [November 21, 2019, 8:22am UTC](https://discourse.slicer.org/t/cant-start-slicer-on-linux-on-one-machine/8175/56 "2019-11-21T08:22:28Z")

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Hi Steve,

Yes I reproduced your building error in Debug mode.

Moreover, in the debug mode, the libArchive has to be changed following your suggestion in  
[https://issues.slicer.org/view.php?id=4616](https://issues.slicer.org/view.php?id=4616)

I’m investigating the libcurl-d.a the “-d” problem and will report back.

–yi

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<div class="post-metadata">

**Author:** ![lassoan](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/lassoan/32/13_2.png) [@lassoan](https://discourse.slicer.org/u/lassoan)\
**Post date:** [November 21, 2019, 12:39pm UTC](https://discourse.slicer.org/t/cant-start-slicer-on-linux-on-one-machine/8175/57 "2019-11-21T12:39:13Z")

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I’ve updated Slicer’s LibArchive version a few days ago. Manual patching should not be necessary anymore.

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<div class="post-metadata">

**Author:** ![gaoyi.cn](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/gaoyi.cn/32/1422_2.png) [@gaoyi.cn](https://discourse.slicer.org/u/gaoyi.cn)\
**Post date:** [November 24, 2019, 10:51am UTC](https://discourse.slicer.org/t/cant-start-slicer-on-linux-on-one-machine/8175/58 "2019-11-24T10:51:13Z")

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Hi Steve,

The curl lib is modified (slightly) so the debug build does not post-fix the “-d”. I’ll create another pull request.

Now it builds on both debug and release modes.

Best,  
yi

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**Author:** ![bpycinski](https://avatars.discourse-cdn.com/v4/letter/b/ecd19e/32.png) [@bpycinski](https://discourse.slicer.org/u/bpycinski)\
**Post date:** [January 21, 2020, 12:33pm UTC](https://discourse.slicer.org/t/cant-start-slicer-on-linux-on-one-machine/8175/59 "2020-01-21T12:33:43Z")

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Hello, I faced the same errors as @gaoyi.cn, on Linux Mint 19, latest git commit, Debug version. But my problem resulted from using system Qt libraries (5.9.5). Change to 5.11.3 from [https://download.qt.io/archive/qt/](https://download.qt.io/archive/qt/) solved the problem.

I just mention it, if anyone else would fall into this issue.

[Previous page](https://discourse.slicer.org/t/cant-start-slicer-on-linux-on-one-machine/8175.md?page=2)