I am happy to be corrected that this is not the case, but from fairly frequent news items it seems to me that sentiment towards Russia in historic East Germany isn't all that negative. Or at least is more positive than West Germany's.
For example, Meduza.io, Nov 6th, about the Ukraine War:
In response to the question “Do you believe that NATO provoked Russia for so long that it had to go to war?” 19 percent of respondents answered in the affirmative. Twenty-one percent said they partially agreed with the idea. That means nearly 40 percent of Germans believe that the cause of the war is unclear and that NATO shares responsibility for it, or even forced Russia into war. In the former GDR in eastern Germany, the share of respondents who answered in the affirmative is 59 percent — making it essentially a mainstream belief.
Or, again, Euronews Feb 2022
In East Germany, once part of the former Soviet bloc, more people (43%) blame the US for intensifying the conflict, compared to the 32% who point the finger at Russia, while in the West, the majority (52%) blames Russia, and only 17% the US, a Forsa survey found last Thursday (3 February).
This is in contrast to many - not all - ex Warsaw Pact countries where anti-Russian sentiment is the norm, sometimes veering into Russophobia. Poland and the Baltics come to mind. Many countries who felt the USSR's boot have no love lost for Russia. And typically, some of the harshest sentiments towards Communism comes from people who lived underneath it. Nor are some East German memories very positive, such as the data protection laws specifically passed remembering the Stasi.
I understand that Germany's overall relationship with Russia, pre-2022, is partially motivated by the very well-founded historical guilt re. WW2. But that effect should affect all of Germany, not be enhanced in ex-East Germany.
And this question, BTW, is not limited to just sentiment about this war - although an answer stating that the war itself is causing a step change in relative East German/West German - Russia sentiment would be a good answer as well.