I have this interesting issue where I am unable to ssh into my server running bionic beaver unless I ping it first. I ran into this issue on another server about a year ago running ubuntu 16, but I fixed it and didn't keep any notes on the problem because I thought it was a weird, one off issue. In that situation, I wasn't able to access any of the services, such as ssh and web, until I had a constant ping going. The kicker is that one of my other Ubuntu servers is able to ssh into this machine without any issues. My workstation is an iMac running High Sierra, and yes, UFW has been disabled.
root@server:/var/log# ufw status Status: inactive root@server:/var/log# aptitude search ssh p erlang-ssh - Erlang/OTP implementation of SSH protocol p libssh-4 - tiny C SSH library (OpenSSL flavor) p libssh-dev - tiny C SSH library. Development files (OpenSSL flavor) p libssh-doc - tiny C SSH library. Documentation files p libssh-gcrypt-4 - tiny C SSH library (gcrypt flavor) p libssh-gcrypt-dev - tiny C SSH library. Development files (gcrypt flavor) i openssh-client - secure shell (SSH) client, for secure access to remote machines i openssh-server - secure shell (SSH) server, for secure access from remote machines i openssh-sftp-server - secure shell (SSH) sftp server module, for SFTP access from remote machines i ssh - secure shell client and server (metapackage) v ssh-client - i ssh-import-id - securely retrieve an SSH public key and install it locally v ssh-server - root@server:/var/log# aptitude show ssh Package: ssh Version: 1:7.6p1-4ubuntu0.2 State: installed Automatically installed: no Priority: optional Section: net Maintainer: Ubuntu Developers <email@example.com> Architecture: all Uncompressed Size: 106 k Depends: openssh-client (>= 1:7.6p1-4ubuntu0.2), openssh-server (>= 1:7.6p1-4ubuntu0.2) PreDepends: dpkg (>= 1.17.5) imac:~ iMac$ ssh -vvv administrator@server OpenSSH_7.6p1, LibreSSL 2.6.2 debug1: Reading configuration data /etc/ssh/ssh_config debug1: /etc/ssh/ssh_config line 48: Applying options for * debug2: ssh_connect_direct: needpriv 0 debug1: Connecting to server port 22. ssh: connect to host server port 22: Operation timed out
Any thoughts on why I would have difficulties getting into this machine from my Mac?