Upgrade from 5.0.8 to 5.1-latest stop with errors on Ubuntu 16.04.4 LTS

Version and requirements information containing plone.app.standardtiles:
[versions] constraint on plone.app.standardtiles: 1.0
Requirement of plone.app.mosaic==2.0rc8: plone.app.standardtiles>=2.2.0
While:
Installing instance.
Error: The requirement ('plone.app.standardtiles>=2.2.0') is not allowed by your [versions] constraint (1.0)

and cannot start

bin/plonectl start
instance: Traceback (most recent call last):
File "bin/plonectl", line 13, in
sys.exit(plone.recipe.unifiedinstaller.ctl.main(server=None, clients=['instance'], location=r'/data/plone5.0.5/plone.almi.at', binDirectory=r'/data/plone5.0.5/plone.almi.at/bin', fileStorage=r'/data/plone5.0.5/plone.almi.at/var/filestorage/Data.fs'))
File "/data/plone5.0.5/buildout-cache/eggs/plone.recipe.unifiedinstaller-4.3.2-py2.7.egg/plone/recipe/unifiedinstaller/ctl.py", line 120, in main
returncode = controller.runCommand(component, command)
File "/data/plone5.0.5/buildout-cache/eggs/plone.recipe.unifiedinstaller-4.3.2-py2.7.egg/plone/recipe/unifiedinstaller/ctl.py", line 83, in runCommand
po = subprocess.Popen(args)
File "/usr/lib/python2.7/subprocess.py", line 711, in init
errread, errwrite)
File "/usr/lib/python2.7/subprocess.py", line 1343, in _execute_child
raise child_exception
OSError: [Errno 2] No such file or directory

any idea?

br Manfred

First do not target Plone-x.x-latest. Always use a precise version, since a -latest version can be a soft-released one and as such 'not recommended for production'. It is the case currently, if you use 5.1-latest you will get at least one problem that did not exist in 5.1. So install in 5.1 and when 5.1.1 is released do the update.

Now for your problem, install a fresh 5.1 in a new directory with the same add-ons versions than your 5.08. Do the appropriate pinnings as necessary since you installed a half-beta add-on.
If it's not possible you can't update with your add-ons, don't even try. If you absolutely want to migrate you will first have to uninstall the problematic add-ons of your current install.

When your new install starts correctly and you can use your add-ons with the empty new Zodb, stop the new instance and copy the old datafiles at the place where your new datafiles are. Restart your new instance, you should have then to migrate the data.

Hi Gp54321

Thanks for your help.

After disabling the pinned Mosaic Version in the buildout.cfg the upgrade worked.

br Manfred