So I’ve been playing with Photon OS recently with a few of our Cloud Provider solutions, very nice lightweight appliance.
However, one thing that surprised me is the minimal/lightweight install does not have ping installed nor can you ping it (ECMP echo replies). In my opinion, this is a basic function for any type of network troubleshooting. I understand it’s minimal…but go cut something else out. 🙂
So how do we set up some basic network functions?
Setting up a Static IP
- cd to /etc/systemd/network
- vi (or use your preferred text editor) a file called 10-eth0.network
- There’s three sections required: Match, Network, and DHCP
- Save it (wq!), and now it’s time to chmod the file so it can be read by the OS
chmod 644 10-eth0.network
- Now we should see the correct permissions:
- Now restart the network daemon service.
systemctl restart systemd-networkd
Installing Ping on Photon OS
- Pretty easy – as you can see, doesn’t exist.
- Now there’s two different versions of Photon – version 1 and 2. On version 1, it’s pretty easy – type in the following:
yum install iputils
- Now for Photon 2.0 (which I’m currently using), repos are disabled by default and so I was getting a message stating “package not found” which was odd. However, digging in further, I found the repos were not enabled.
Enabling Repos so we can pull iputils
- I enabled three repos:
- We need to edit each file and change the enabled=0 to enabled=1
- Once I did this, run “tdnf repolist” and we should now see the following:
- Now let’s install it!
tdnf install iputils
- Now we should see the following:
- Sucess! Ping is available now, along with netstat too.
Allow ICMP echo responses
- This is a change in the firewall table. By default, ICMP echo and replies are dropped.
- Here are the two commands required to enable ICMP traffic:
iptables -A OUTPUT -p icmp -j ACCEPT iptables -A INPUT -p icmp -j ACCEPT
- Before I make the change on my system, I’m unable to ping
- Make the iptables change….
- Voila! We now get a response.
One last tidbit – SSHD not starting?
- During some of my testing, my lab environment went bottoms up – thanks, Timo 😉
- After my Photon appliances started back up, I could not SSH to them. So after some troubleshooting and help from the VMware internal team, figured out what happened.
- Steps to resolve:
- Log into the console and ls -l /var/vmware/skip_sshd and you can also check the status of sshd by typing “systemctl status sshd”
- If the file does exist, you need to remove it. No clue why it was added when I had a hard power outage, but it did.
- Now start up ssh..
systemctl start sshd
- Voila! we can now see it’s started
- Now, SSH works!
Other great details on Photon commands can be found here: Photon OS Troubleshooting Guide