zmap: Could not create zc cluster: No buffer space available

[hagna]

While trying to get zmap to use pfring this command:

./src/zmap -i zc:enp0s4 -p 80 -o o -T5

gives this error:

Mar 11 15:35:06.210 [FATAL] zmap: Could not create zc cluster: No buffer space available

This is for ubuntu 20.04.4 kernel 5.13.0-35-generic and pf_ring 33e58fe4 (Thu Mar 10 18:34:12 2022 +0100)

[ljluestc]

Increase Buffer Space:

You can try increasing the amount of buffer space available for network operations. This can involve modifying kernel parameters related to network buffers.
Edit the /etc/sysctl.conf file and add or modify entries like:
``
net.core.rmem_max = 16777216
net.core.wmem_max = 16777216
net.core.rmem_default = 1048576
net.core.wmem_default = 1048576

After editing the file, apply the changes by running:

sudo sysctl -p

Check Resource Usage:

Make sure your system is not running out of memory or other critical resources.
Use tools like free and top to monitor memory usage.
Check pfring Configuration:

Review the pfring configuration to ensure it's set up correctly and not causing any conflicts.
Check for any issues related to Zero Copy (zc) support in pfring.
Kernel Update:

Check if there are any updates to the kernel or pfring that might address this issue.
Sometimes, upgrading to a newer kernel or pfring version can resolve problems related to buffer space.
Resource Limits:

Check if there are resource limits set on the user running ZMap that might be affecting buffer space allocation.
Networking Hardware:

Ensure that the network interface card (NIC) and driver support Zero Copy (zc) technology and pfring.
Kernel Module Parameters:

Some kernel modules and drivers have parameters that control buffer space. You might want to investigate if there are relevant parameters for your network device.