Why does git pull/push, traceroute take so long?

Question

git

Hello!
The problem is this. There is a local grid that the router spreads in my office. My work machine is connected to it. The router itself is part of our corporate network, in which there is a gitlab server.
If I do a traceroute (or, for example, git push/pull) with the server name - gitlab.ipb.uni-bonn.de, this action takes a long time (10 seconds). If I do the same but using his real ip, then everything happens quickly as it should. Moreover, the traceroute output is exactly the same.
Tell me, please, what can it be? Where to dig?
Thanks in advance.
UPD: if I do
dig 8.8.8.8 gitlab.ipb.uni-bonn.deI get a reasonable response in the form of the correct ip address.

Answer 1

DNS is slow. Or one of the DNS specified in the system settings does not respond at all.

Answer 2

As an option, the local wrapper is mocking
Now avahi is fashionable, there is still samba\winbind, yp, ldap, etc. Wrapper can be called in NSS, pam. Avahi seems to have some other hooks for libc.
Another option - a semi-working ipv6 lives on the network, but it seems to have been fixed everywhere (gai.conf)
One way or another, there is a problem with the resolver