---
title: "Gateway - Crash after \"Too many open files\" error is logged"
description: "The Gateway may crash after logging a \"Too many open files\" error due to system resource limits. Adjusting user, global, or SystemD service file limits resolves this by increasing allowed open files and processes."
url: "https://docs.itrsgroup.com/docs/faq/geneos/360023639854-geneos-gateway-crash-after-too-many-open-files-error-is-logged/index.html"
---
## The Problem

I'm getting the following error in my Gateway log file.

```
<Thu May 23 08:15:48> INFO: Translator ConManager accept() failed. Details: 'checkListenPortActivity()'; ''; errno=24 (Too many open files)
```

## Potential Causes of File Limit Errors

While SystemD provides automation for system reboots, it also enforces security measures that limit resource consumption. The error may stem from the following:

- **SystemD Service Constraints:** Limits on how many files a daemon can open while the SystemD control script owns the process.
- **User-Level ulimits:** Constraints specific to the user account running the process.
- **Global/Kernel ulimits:** System-wide limits defined within the Linux kernel or global configuration.

If you are bypassing the `gatewayctl` script to leverage SystemD service files directly, you must explicitly define resource limits within your **Service Unit file**.

- `LimitNOFILE=<value>`
- `LimitNPROC=<value>`

> **Note:** Because "ulimits" can be set at various levels (user, global, or kernel), consult your RHEL SysAdmin to ensure these values align with your specific environment's requirements.

## To Investigate further

Use the commands below:

- To get the open files limit for the user running the netprobe process.

```
ulimit -a

#Sample output below

testuser@TestingEnvironment:~$ ulimit -a
real-time non-blocking time  (microseconds, -R) unlimited
core file size              (blocks, -c) 0
data seg size               (kbytes, -d) unlimited
scheduling priority                 (-e) 0
file size                   (blocks, -f) unlimited
pending signals                     (-i) 31445
max locked memory           (kbytes, -l) 1016536
max memory size             (kbytes, -m) unlimited
open files                          (-n) 1024
pipe size                (512 bytes, -p) 8
POSIX message queues         (bytes, -q) 819200
real-time priority                  (-r) 0
stack size                  (kbytes, -s) 8192
cpu time                   (seconds, -t) unlimited
max user processes                  (-u) 31445
virtual memory              (kbytes, -v) unlimited
file locks                          (-x) unlimited
```

```
ulimit -n

#Sample output below

testuser@TestingEnvironment:~$ ulimit -n
1024
```

- To get the max open files limit for the netprobe process itself:

```
cat /proc/<PID>/limits

#Sample output below

testuser@TestingEnvironment:~$ cat /proc/4193/limits
Limit                     Soft Limit           Hard Limit           Units
Max cpu time              unlimited            unlimited            seconds
Max file size             unlimited            unlimited            bytes
Max data size             unlimited            unlimited            bytes
Max stack size            8388608              unlimited            bytes
Max core file size        0                    unlimited            bytes
Max resident set          unlimited            unlimited            bytes
Max processes             31445                31445                processes
Max open files            1024                 1048576              files
Max locked memory         1040932864           1040932864           bytes
Max address space         unlimited            unlimited            bytes
Max file locks            unlimited            unlimited            locks
Max pending signals       31445                31445                signals
Max msgqueue size         819200               819200               bytes
Max nice priority         0                    0
Max realtime priority     0                    0
Max realtime timeout      unlimited            unlimited            us
```

```
cat /proc/<PID>/limits | grep "Max open files"

#Sample output below

testuser@TestingEnvironment:~$ cat /proc/4193/limits | grep "Max open files"
Max open files            1024                 1048576              files
```

- The number of entries in this directory corresponds to the number of open file descriptors used by the netprobe.

```
ls -l /proc/<PID>/fd | wc -l

#Sample output below

testuser@TestingEnvironment:~$ ls -l /proc/4193/fd | wc -l
6
```

```
ls -l /proc/<PID>/fd

#Sample output below

testuser@TestingEnvironment:~$ ls -l /proc/4193/fd
total 0
lrwx------ 1 testuser testuser 64 Feb  6 12:56 0 -> /dev/pts/1
lrwx------ 1 testuser testuser 64 Feb  6 12:56 1 -> /dev/pts/1
lrwx------ 1 testuser testuser 64 Feb  6 12:56 2 -> /dev/pts/1
l-wx------ 1 testuser testuser 64 Feb  6 12:56 3 -> /home/testuser/netprobe731/netprobe/netprobe.log
lrwx------ 1 testuser testuser 64 Feb  6 12:56 4 -> 'socket:[35317]'
```

## The Solution

The error message "too many open files" is a system/OS issue telling the netprobe it has run out of resources. Please work with your infra/Unix team to adjust the limits.

You can also edit your /etc/systemd/system/<gateway start script> and add the following to your [Service] section:

```
LimitNOFILE=#####

LimitNPROC=#####
```

Where # is the recommended maximum number of open files and processes allowed/determined by your Systems Administrator.