AutoScheduling Issue when Dependency is created on SNET Child Task


#1

Hi,
Can you please help us regarding below issue

T1 ASAP, Start Date 19 Jan
T2 Start No Earlier Than Having Constraint Date 20 Jun and Start Date 20 Jun
T21(Parent T2), ASAP Having Start Date 20 Jun

when FS dependency is created, on T21 with T1(i.e T1 predecessor, and T21 Successor), expectation is nothing should happen .
BUT auto scheduling is moving T21 to 20 Jan which is WRONG.(why wrong ? T2 is having start no earlier than constraint date 20 Jun, child of T2 cannot start before 20 Jun !!)

Do we have any workaround for this ?

Here is the screenshot showing issue, Parent SNET task is having constraint date 04 sep 2019, adding dependency on Child Task of SNET is making child start before its parent start


#2

Hello,
If the type of the T2 task is task, it works as expected because T2 and T21 tasks are not linked. And regular tasks are not related to one another any other way.
So, you need to link T2 and T21 and create a link from T1 to T2, then it will work as you expect.

If the type is project (I don’t think it is the case according to the screenshot), T2 ignores the date parameters, and it will move to the same dates as T21. Adding constraints to project tasks won’t make any effect. If you want to make it work that way, you need to implement a custom solution by using Gantt API and Javascript.


#3

@ramil,
Thank you so much for the reply.

and you are right, in our case T2 Type is project. so when T2 type is project, constraint dates at T2 is not honored. is it ?
i am confused here, can you please help me understand , since T21 is created under T2 directly, implicitly T21 is a child of T2 right ? still we need to create a link ?

I am not sure how to create a link between T2 and T21.
can you please point me to the relevant documentation/example where i can create a link.

Thank you again for the help.


#4

Hello,

and you are right, in our case T2 Type is project. so when T2 type is project, constraint dates at T2 is not honored. is it ?

Yes, and it is specified in the following article:
https://docs.dhtmlx.com/gantt/desktop__auto_scheduling.html#timeconstraintsfortasks

Well, if T2 is a project, you cannot add a link to its child task. So, you need to add the SNET constraint to the T21 task, and it should work correctly:


#5

Thank you so much for clarification and Help.