MySQL Error - (SSH) Channel open failure: Too many open files

[jhambach]

Describe the problem/error/question

After a period of time, the MySQL node will return the error in the title. Same issue from this post:

Problem in node ‘MySQL‘ (SSH) Channel open failure After a period

I installed n8n through cloudron and have been using it for a long time, but when changing from VPS with Backup, it seems that n8n works normally, performs its processes, but after a time on it simply starts to give error in all jobs in the part of connecting to Mysql in which I use SSH, I get the following error: Problem in node ‘MySQL’(SSH) Channel open failure: Connection refused The error disappears if I restart the N8N by Cloudron Repair, but after a while the error happens again, I can’t…

What is the error message (if any)?

(SSH) Channel open failure: Too many open files

Resolution

Restarting n8n fixes the issue, but it inevitably comes back

Attempted Solution

I’ve tried increase the no file limits in /etc/security/limits.conf to the following:

• soft nofile 4096
• hard nofile 4096

I’ve also verified pam_limits is set correctly.

I then restarted it, but it still seems to be getting set to 1024

However, when I check ulimit -Sn it returns 1024. ulimit -Hn returns 4096

Bandaid Solution

I’ve been using the error trigger with the Execute Command node to restart n8n if it gets that error. Any long term solutions to this would be appreciated

Information on your n8n setup

• n8n version: 1.75.2
• Database (default: SQLite): postgresdb
• n8n EXECUTIONS_PROCESS setting (default: own, main): Main
• Running n8n via (Docker, npm, n8n cloud, desktop app): npm
• Operating system: Ubuntu 22

[j4b3r]

@jhambach

Too many open files

you must do this steps on your ubuntu server:
first check current setting :

ulimit -n

edit /etc/sysctl.conf and add this line:

fs.file-max = 65535

afther tha run this command to load this seeting

sudo sysctl -p

edit /etc/security/limits.conf and add:

root soft     nproc          65535    
root hard     nproc          65535   
root soft     nofile         65535   
root hard     nofile         65535

edit /etc/pam.d/common-session and add:

session required pam_limits.so

log out and login again and check new limits with this command:

ulimit -n

Restart n8n