ssh fails to connect but scp works in gitlab-ci - ssh

Question

I am using gitlab secrets to pass the ssh private key for it to connect to a remote server. For scp works fine but running ssh doesn't.
I can even see the ssh logs on the server when the gitlab pipeline runs and tries to do ssh.
Here is the output from gitlab-pipeline:
ssh -i /root/.ssh/id_rsa -vvv root#$DEPLOYMENT_SERVER_IP "docker login -u ${CI_REGISTRY_USER} -p ${CI_REGISTRY_PASSWORD} ${CI_REGISTRY};"
OpenSSH_7.6p1 Ubuntu-4ubuntu0.3, OpenSSL 1.0.2n 7 Dec 2017
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: /etc/ssh/ssh_config line 19: Applying options for *
debug2: resolving "157.245.xxx.xxx" port 22
debug2: ssh_connect_direct: needpriv 0
debug1: Connecting to 157.245.xxx.xxx [157.245.xxx.xxx] port 22.
debug1: connect to address 157.245.xxx.xxx port 22: Connection refused
ssh: connect to host 157.245.xxx.xxx port 22: Connection refused
Here is my gitlab pipeline which fails:
deploy_production:
stage: deploy
image: python:3.6-alpine
before_script:
- 'which ssh-agent || ( apk update && apk add openssh-client)'
- eval "$(ssh-agent -s)"
- mkdir -p ~/.ssh
- chmod 700 ~/.ssh
- echo "$DEPLOY_SERVER_PRIVATE_KEY" | tr -d '\r' > ~/.ssh/id_rsa
- chmod 600 ~/.ssh/id_rsa
- ssh-add ~/.ssh/id_rsa
- apk add gcc musl-dev libffi-dev openssl-dev iputils
- ssh-keyscan $DEPLOYMENT_SERVER_IP >> ~/.ssh/known_hosts
- chmod 644 ~/.ssh/known_hosts
script:
- scp -r ./docker-compose.yml root#${DEPLOYMENT_SERVER_IP}:~/
- scp -r ./env/production/docker-compose.yml root#${DEPLOYMENT_SERVER_IP}:~/docker-compose-prod.yml
- ssh -i /root/.ssh/id_rsa -vvv root#$DEPLOYMENT_SERVER_IP "docker login -u ${CI_REGISTRY_USER} -p ${CI_REGISTRY_PASSWORD} ${CI_REGISTRY};"
environment: production
only:
- "master"
sshd auth logs:
sshd[27552]: Connection closed by 35.231.235.202 port 53870 [preauth]
sshd[27554]: Connection closed by 35.231.235.202 port 53872 [preauth]
sshd[27553]: Connection closed by 35.231.235.202 port 53874 [preauth]
sshd[27558]: Accepted publickey for root from 35.231.235.202 port 53876 ssh2: RSA SHA256:bS8IsyG4kyKcTtfrW+h4kw1JXbBSQfO6Jk6X/JKL1CU
sshd[27558]: pam_unix(sshd:session): session opened for user root by (uid=0)
systemd-logind[945]: New session 649 of user root.
sshd[27558]: Received disconnect from 35.231.235.202 port 53876:11: disconnected by user
sshd[27558]: Disconnected from user root 35.231.235.202 port 53876
sshd[27558]: pam_unix(sshd:session): session closed for user root
systemd-logind[945]: Removed session 649.
sshd[27560]: Received disconnect from 222.186.15.160 port 64316:11: [preauth]
sshd[27560]: Disconnected from authenticating user root 222.186.15.160 port 64316 [preauth]
sshd[27685]: Accepted publickey for root from 35.231.235.202 port 53878 ssh2: RSA SHA256:bS8IsyG4kyKcTtfrW+h4kw1JXbBSQfO6Jk6X/JKL1CU
sshd[27685]: pam_unix(sshd:session): session opened for user root by (uid=0)
systemd-logind[945]: New session 650 of user root.
sshd[27685]: Received disconnect ected by user
sshd[27685]: Disconnected from user root 35.231.235.202 port 53878
sshd[27685]: pam_unix(sshd:session): session closed for user root
systemd-logind[945]: Removed session 650.

Answer 1

Finally figured out why is this happening. I see that the issue is with the ufw firewall rule for ssh on my server. It is rate limited and since in my gitlab-pipeline I am doing scp 2 times followed by ssh which is possibly happening too quick, the server refuses the connection.
It works outside of gitlab pipeline as doing it manually would be slow.