Two Tezos jobs use same network port at same time

[moyodiallo]

Hi
This issue is about when Tezos test runs at same time on 4.12.0 and 4.12.0+domains, when the network port is used by one run and the other can't because of the same port.

┌──────────────────────────────────────────────────────────────────────────────┐
│ [FAIL]        p2p-connection-pool          0   simple.                       │
└──────────────────────────────────────────────────────────────────────────────┘
idtrCxjv3sZz:55011: PID: 90231
idtkRJrL9kyd:55012: PID: 90232
idrMpPQSJvjj:55013: PID: 90233
idqdTzCbGwVN:55014: PID: 90234
idsfoLeD3FnX:55015: PID: 90235
idqhVnG4DM3Q:55016: PID: 90236
idrLqLUQrdPJ:55017: PID: 90237
ids7Em5CA9eM:55018: PID: 90238
idtHthjZZWXj:55019: PID: 90239
idqn6hcKfRGe:55020: PID: 90240
idtkRJrL9kyd:55012: Detached process ended with error.Error:
idtkRJrL9kyd:55012:                                     An error occured while initializing P2P server on this address: 127.0.0.1:55012.
idtkRJrL9kyd:55012:                                       Reason: Address already in use.
idtkRJrL9kyd:55012:                                       Another tezos node is probably running on this address.
idtkRJrL9kyd:55012:                                       Please choose another P2P port using --net-addr.
idtkRJrL9kyd:55012: 
idtkRJrL9kyd:55012: 
idqdTzCbGwVN:55014: Detached process ended with error.Error:
idqdTzCbGwVN:55014:                                     An error occured while initializing P2P server on this address: 127.0.0.1:55014.
idqdTzCbGwVN:55014:                                       Reason: Address already in use.
idqdTzCbGwVN:55014:                                       Another tezos node is probably running on this address.
idqdTzCbGwVN:55014:                                       Please choose another P2P port using --net-addr.
idqdTzCbGwVN:55014: 
idqdTzCbGwVN:55014: 
Nov 24 15:23:02.696 - process: Early error! Canceling remaining process.
Nov 24 15:23:02.696 - process: The processes 0(idtrCxjv3sZz:55011:) 2(idrMpPQSJvjj:55013:)
Nov 24 15:23:02.696 - process:               3(idqdTzCbGwVN:55014:) 4(idsfoLeD3FnX:55015:)
Nov 24 15:23:02.696 - process:               5(idqhVnG4DM3Q:55016:) 6(idrLqLUQrdPJ:55017:)
Nov 24 15:23:02.696 - process:               7(ids7Em5CA9eM:55018:) 8(idtHthjZZWXj:55019:)
Nov 24 15:23:02.696 - process:               9(idqn6hcKfRGe:55020:) 
Nov 24 15:23:02.696 - process:      have been canceled.
Nov 24 15:23:02.696 - process: The process 1(idtkRJrL9kyd:55012:) 
Nov 24 15:23:02.696 - process:     failed with error:
Nov 24 15:23:02.696 - process:     Error:
Nov 24 15:23:02.696 - process:       An error occured while initializing P2P server on this address: 127.0.0.1:55012.
Nov 24 15:23:02.696 - process:         Reason: Address already in use.
Nov 24 15:23:02.696 - process:         Another tezos node is probably running on this address.
Nov 24 15:23:02.696 - process:         Please choose another P2P port using --net-addr.
Nov 24 15:23:02.696 - process: 
Nov 24 15:23:02.696 - process: 
Nov 24 15:23:02.696 - process: 
[failure] Error:
  The processes 0(idtrCxjv3sZz:55011:) 2(idrMpPQSJvjj:55013:)
                3(idqdTzCbGwVN:55014:) 4(idsfoLeD3FnX:55015:)
                5(idqhVnG4DM3Q:55016:) 6(idrLqLUQrdPJ:55017:)
                7(ids7Em5CA9eM:55018:) 8(idtHthjZZWXj:55019:)
                9(idqn6hcKfRGe:55020:) 
       have been canceled.
  The process 1(idtkRJrL9kyd:55012:) 
      failed with error:
      Error:
        An error occured while initializing P2P server on this address: 127.0.0.1:55012.
          Reason: Address already in use.
          Another tezos node is probably running on this address.
          Please choose another P2P port using --net-addr.

I discussed with @talex5, he noticed to me it's caused by the parameter network host of a run (oBuilder). With this generated script we can see the parameter:

(run (cache (opam-archives (target /home/opam/.opam/download-cache)))
                   (network host)
                   (shell "opam exec -- bash -c 'source $HOME/.poetry/env; source $HOME/.cargo/env; make build-deps && eval $(opam env); PATH=\"$HOME/.local/bin:$PATH\"; make -C tests_python install-dependencies && make && make test'"))

The configuration is in this file

ocaml-multicore-ci/service/conf.ml

Line 147 in 3c06080

| "tezos" -> `Script ["sudo apt-get install -y rsync git m4 build-essential patch unzip wget pkg-config libgmp-dev libev-dev libhidapi-dev libffi-dev opam jq zlib1g-dev bc autoconf software-properties-common"; "gpg --keyserver keyserver.ubuntu.com --recv-keys BA6932366A755776"; "gpg --export BA6932366A755776 | sudo apt-key add -"; "sudo add-apt-repository 'deb http://ppa.launchpad.net/deadsnakes/ppa/ubuntu bionic main'"; "sudo apt-get update"; "sudo apt-get install -y python3.9 python3.9-dev python3.9-distutils python3-pip virtualenv python3.9-venv"; "wget https://sh.rustup.rs/rustup-init.sh"; "chmod +x rustup-init.sh"; "./rustup-init.sh --profile minimal --default-toolchain 1.52.1 -y"; "opam install dune"; "curl -sSL https://raw.githubusercontent.com/python-poetry/poetry/master/install-poetry.py | python3.9 -"; "python3.9 -m pip install --upgrade setuptools"; "bash -c 'source $HOME/.poetry/env; source $HOME/.cargo/env; make build-deps && eval $(opam env); PATH=\"$HOME/.local/bin:$PATH\"; make -C tests_python install-dependencies && make && make test'"]

There's no alternative to avoid the parameter network host for solving this issue when configuring(config.ml) because Script variant is generated with.

[moyodiallo]

to solve this issue, I think we have to add a new variant without network host parameter. Like Script_nohost to handle those kind of script