how to synchronize two servomotors

you can't drive the signal x-pos-fb from two sources so

net x-pos-fb <= hm2_5i25.0.encoder.02.position #loop closed with encoder
net x-pos-fb <= hm2_5i25.0.stepgen.08.position-fb #loop closed with local stepgen feedback

Cannot both be present in the hal file, you would select one or the other based on whether you were
using encoder feedback or local stepgen feedback

Also #net x-pos-fb => axis.0.motor-pos-fb

must be uncommented or you will get an immediate following when you move, since LinuxCNCs
feedback position will not be updated and therefore not match the commanded position

yeah sry I allready correct me I # out the right one. In open loop everything is fine an I can get high velocitys. In closed loop I have the following error issues.

Following errors with closed loop are to be expected until you get the pid loops properly tuned. Open up the min and max following errors in the ini file to 20-30mm while you tune the pid loops. Then after you have it all working right, put them back to their correct small settings.

Can you post your current HAL/INI files?

Your plots look like FF1 is incorrect (they have a ferror proportional to velocity)

Also is it possible that the position loops in the servo drives are not tuned good enough? Resulting in when you are running open loop you don't see how far off the motor error is, but when you add the encoder feedback Linuxcnc is expecting better motor control than the drives are giving with their current state of tune.

When you post plots of halscope, use a screen shot rather than photos of the computer screen.
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