this post was submitted on 01 Jul 2024
235 points (99.6% liked)
Linux
48328 readers
540 users here now
From Wikipedia, the free encyclopedia
Linux is a family of open source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991 by Linus Torvalds. Linux is typically packaged in a Linux distribution (or distro for short).
Distributions include the Linux kernel and supporting system software and libraries, many of which are provided by the GNU Project. Many Linux distributions use the word "Linux" in their name, but the Free Software Foundation uses the name GNU/Linux to emphasize the importance of GNU software, causing some controversy.
Rules
- Posts must be relevant to operating systems running the Linux kernel. GNU/Linux or otherwise.
- No misinformation
- No NSFW content
- No hate speech, bigotry, etc
Related Communities
Community icon by Alpár-Etele Méder, licensed under CC BY 3.0
founded 5 years ago
MODERATORS
you are viewing a single comment's thread
view the rest of the comments
view the rest of the comments
Question if I update my server and it has the new SSH (patched) package. Is that enough or do I have to restart the server as well? How can I check if the old SSH is in use currently?
we do restarts twice a month, they are in production
Well I should have read the first comment before I went ahead with update and reboot😪
Some package managers have a command to see if anything is in need of restart. Zypper has ps -s for example. I'd restart to be sure though.
My server tells me a restart would be required because of:
Does that have anything to do with the SSH package?
It sounds like it's the kernel but whether it has anything to do with ssh, I really don't know. Sometimes parts work together in surprising ways, as I learned with the recent sshd/systemd/xz exploit.
You might be fine and this was the most alarming exploit since it's very inconvenient, but personally I'd restart just to be sure.
No - it's the kernel image - the actual operating system, rather than a service that runs on top of it.
If you just want to restart your ssh service after updating the packages, then "systemctl restart sshd" is all that's needed, although you should probably reboot whenever the package manager suggests as a general good habit.
For anyone in RHEL / Fedora land (or using dnf somewhere else), try
dnf needs-restartingto list executables that have mismatched files on disk vs memory. The-rflag will hint if a reboot is needed (due to things like kernel or glibc changes)The packages in most distros will also restart the server for you. Any existing SSH sessions will technically be running in vulnerable versions, but if I'm understanding the vulnerability correctly this isn't a problem, as they won't be trying to authenticate a user.
If you want to be sure, you can manually restart the ssh server yourself. On most distros
sudo systemctl restart sshdshould do it.