Leonid Shulov wrote:

After I have upgraded amanda in server side to 2.4.5p1-2 version it stoped backup.

How did you upgrade?
If compiling from source, you must "make install" as root.
If not, the install process cannot set the permissions correct,
and Amanda will not work.

If it were rpms, which ones?

It is easiest if you just reinstall as root.
Otherwise, from the list below, the client is correct.

In log file of amdump I see:

 dumper: FATAL must be run setuid root to communicate correctly

Which permission  should be installed?
In server side permissions is:
-rwxr-xr--    1 root disk    30628 Dec 29 21:00 dumper
-rwxr-xr--    1 root disk     5660 Dec 29 21:00 killpgrp
-rwxr-xr-x    1 root root     4810 Dec 29 20:59 patch-system
-rwxr-xr--    1 root disk    35608 Dec 29 21:00 planner
-rwxr-xr--    1 root disk     4764 Dec 29 21:00 rundump
-rwxr-xr--    1 root disk     5048 Dec 29 21:00 runtar
-rwxr-xr-x    1 root root    18140 Dec 29 21:00 selfcheck
-rwxr-xr-x    1 root root    31912 Dec 29 21:00 sendbackup
-rwxr-xr-x    1 root root    29624 Dec 29 21:00 sendsize
-rwxr-xr-x    1 root root    33004 Dec 29 21:00 taper

In clien side permissions is:
-rwsr-x---    1 root   disk 146848 Mar 22  2005 dumper
-rwsr-x---    1 root   disk  19980 Mar 22  2005 killpgrp
-rwxr-xr-x    1 amanda disk   4810 Mar 22  2005 patch-system
-rwsr-x---    1 root   disk 148308 Mar 22  2005 planner
-rwsr-x---    1 root   disk  19036 Mar 22  2005 rundump
-rwsr-x---    1 root   disk  19184 Mar 22  2005 runtar
-rwxr-xr-x    1 root   root  78416 Mar 22  2005 selfcheck
-rwxr-xr-x    1 amanda disk  97692 Mar 22  2005 sendbackup
-rwxr-xr-x    1 amanda disk  90972 Mar 22  2005 sendsize

PS. When I changed dumper permission to -rwsr-x--- its not help.

But I guess the error message changes: e.g. planner also needs
to have correct permissions.