bobpeers -> blog

I only recently discovered that when I upgrade my Diskstations firmware my SSH settings are wiped out. This includes the /etc/ssh/sshd_config file plus the certificate located at /root/.ssh/.

It’s not like I upgrade the firmware that often but it’s annoying that I have to go through this procedure every time I do.

I see the latest firmware also has an enable SSH option but I’d really like to see this expanded into a full SSH interface, allowing for different ports, not allowing password logins, certificate generation etc.

WordPress Directory Permissions

While I was upgrading my blog to WordPress 2.6 I noticed some strange files in my upload directory. As suggested in the WordPress codex my upload directory permissions were set to be world writeable (777) since this was required my my web host but it seems that someone has exploited this hole and uploaded files there. On top of that they then get linked by Google so searches on my site show content from the uploaded pages.

I’ve since disabled the WordPress upload capability by changing the directory permissions and I advise you to do the same. This page echoes my sentiments well.

I’ve also discovered that my Diskstation no longer shuts down or reboots when the commands are issues over an SSH connection. There’s a thread on the Synology forum describing the same problem, it seems to be the 0637 firmware that’s causing this.

The Diskstation stays running but refuses all connection via http, SSH, cifs or any other method. The only way to fix is to turn it off using the button on the front panel.

I’ll download and install the 0640 firmware tonight and see if it fixes the issue.

Update – Just installed the 0640 firmware and it still doesn’t work, it’s also a bit hard to debug since the SSH connection is lost so you’re working in the dark.

After getting SSH working on my Diskstation DS-106e so I can log in using a public/private key I’m thinking about installing the GNU screen program. This is incredibly useful as it allows a single terminal to host multiple sessions so you can, for example, start a session to download a large file and then open a new session and continue working. Even more so over SSH as you only get one terminal per SSH connection so it avoids opening multiple SSH connection just to run multiple commands.

You can also detach the sessions, log off from the SSH session and then later log back on, reattach the session and continue from where you left off. It’s really useful for long running tasks that you need to monitor.

There’s a great Red Hat Magazine article showing the basics plus how to set up a .screenrc config file to automatically start sessions or add a status bar to the bottom.

The only other option is to use the nohup command but this does not allow for monitoring progress of a program.

The main problem is that to install screen I need to first install bootstrap but like many people I’m slightly afraid of bricking my Diskstation.

Maybe I’ll add this to the Synology feature request forum in the meantime.

Diskstation Port 80 not responding

On a related note if I enter the admin pages for my Diskstation and enable https connections then my Diskstation no longer listens on port 80, I’ll have to look into this more when I have the time.