I’ve been hitting a bit of a snag on my Ubuntu 18.04 setup, and I’m not sure where to turn for help. I’m running a couple of services that are pretty file-intensive, and I keep getting this annoying error about reaching the maximum number of open files. It’s incredibly frustrating because it’s interrupting my workflow and causing applications to crash.
I did some digging and found that there’s a default limit on the number of open files, which seems to be around 1024. I can only imagine how that might have been set ages ago, but with the kind of projects I’m working on, I absolutely need to raise that limit.
I’ve tried a few things, like checking the `/etc/security/limits.conf` file to adjust the settings there, but I’m not 100% clear on how to do it correctly. I read somewhere that you need to add lines like `* soft nofile 4096` and `* hard nofile 8192`. But then I started worrying about whether that would actually work or if it would just mess things up even more.
Also, I’m somewhat confused about the difference between soft and hard limits. Do I need to adjust one but not the other? And should I be doing this as the root user, or can I just be using my regular account?
If any of you have tackled this before or have some steps you can share, I’d really appreciate your advice. It would be awesome to know not just how to raise the limit, but also any potential pitfalls I should watch out for. Like, is there a chance to crash my system if I go too high, or can I just set it to something like 20,000 and call it a day?
Thanks in advance for any insights!
To address the issue of reaching the maximum number of open files on your Ubuntu 18.04 setup, you can indeed modify the limits as specified in the `/etc/security/limits.conf` file. Adding the lines `* soft nofile 4096` and `* hard nofile 8192` is a good approach to increasing these limits. The soft limit is the value you can change while the hard limit is a ceiling that can’t be exceeded without superuser privileges. Typically, you would edit this file as the root user to ensure changes take effect system-wide. For common applications, setting the soft limit to 4096 and the hard limit to 8192 is generally safe and should alleviate the frustration caused by hitting the default limit of 1024.
However, it is wise to be cautious when setting these values, as extremely high limits—such as 20,000—could lead to performance issues or instability under certain conditions. It’s advisable to gradually increase the limits and monitor system performance. After editing the `limits.conf` file, you can verify the changes by restarting your services or logging out and back in. To check the current limits in a terminal, you can use the command `ulimit -n`. Additionally, make sure that your services are started after these changes take effect to ensure they inherit the new limits. If you notice any adverse effects, you can always revert the changes back to their original state.
If you’re running into that annoying “too many open files” error, you’re definitely not alone! It’s common when running file-intensive services, and adjusting the limits is a good way to solve it.
You’re right that the default limit is usually set to 1024. The lines you found to add to `/etc/security/limits.conf` are spot on:
Here’s a quick rundown of what those settings mean:
So, you might want to tweak both limits. As for whether you should do this as root or a regular user, you’ll need superuser privileges to edit the `limits.conf` file, but once you’ve done that, the new limits should apply to your regular users next time they log in.
As for concerns about crashing your system, it’s generally safe to raise the limits, but you might not want to go overboard. Setting it too high, like 20,000, might be unnecessary and could lead to resource exhaustion. A good practice is to gradually increase the limit until your service runs smoothly.
After you make changes to `/etc/security/limits.conf`, you’ll want to either log out and back in or restart your services for the changes to take effect. This is key to ensuring that your applications pick up the new limits.
Lastly, keep an eye on system performance after making these changes. If you notice any unusual behavior, you can always revert to the original settings. Good luck, and happy coding!