'nslookup' tool missing while executing "./build.sh -b l4v"

[GooTal]

I cloned this repo and executed this command "./build.sh -b l4v", then got message :

.....
cabal-install    > Linking .stack-work/dist/x86_64-linux-tinfo6/Cabal-3.4.1.0/build/cabal/cabal ...
cabal-install    > copy/register
cabal-install    > Installing executable cabal in /root/.stack/snapshots/x86_64-linux-tinfo6/f04d0d45be1db2d1a4535c7134bb900ee49fac5cd84a673d5abb9a8554c6afdd/9.0.2/bin
Completed 22 action(s).
stack exec -- ./stack-path cabal v2-update
Config file path source is default config file.
Config file /root/.cabal/config not found.
Writing default configuration to /root/.cabal/config
Warning: 'nslookup' tool missing - can't locate mirrors

I waited for an hour and it seems stucked here.

So i added dnsutils in scripts/l4v.sh and got no warning about nslookup. But it still stucked here:

.....
cabal-install    > Linking .stack-work/dist/x86_64-linux-tinfo6/Cabal-3.4.1.0/build/cabal/cabal ...
cabal-install    > copy/register
cabal-install    > Installing executable cabal in /root/.stack/snapshots/x86_64-linux-tinfo6/f04d0d45be1db2d1a4535c7134bb900ee49fac5cd84a673d5abb9a8554c6afdd/9.0.2/bin
Completed 22 action(s).
stack exec -- ./stack-path cabal v2-update
Config file path source is default config file.
Config file /root/.cabal/config not found.
Writing default configuration to /root/.cabal/config

Did I miss something? Any idea to solve this problem? Thanks a lot.