What is the kernel parameter net.ipv4.conf.all.log_martians for?
Environment
- Red Hat Enterprise Linux
- IPv4 networking
Issue
What is the kernel parameter net.ipv4.conf.all.log_martians for?
How to disable martin log creation?
Resolution
The kernel parameter net.ipv4.conf.all.log_martians is used to control logging when the kernel receives a packet with an impossible source or destination address.
The log_martians parameter can also be controlled for all current interfaces with all, or per-interface for example net.ipv4.conf.eth0.log_martians
To make the changing of this tunable permanent, it can be set in /etc/sysctl.conf such as:
Below sysctl parameter will enable the martians logs for all interfaces
net.ipv4.conf.all.log_martians = 1
If you want to disable martian logs for all interfaces then add the below parameter into "/etc/sysctl.conf"
net.ipv4.conf.all.log_martians = 0
If you want to disable martian logs for only particular interfaces then add the below parameter into "/etc/sysctl.conf"
## Syntax:
net.ipv4.conf.<interfacename>.log_martians = 0
## Note:
0 --> Indicate disable martians logs
1 --> Indicate enable martians logs
## Example:
net.ipv4.conf.eth0.log_martians = 0
This will be applied at system boot and can be applied during runtime with the sysctl -p command.
Root Cause
The concept of a martian source is described further at:
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