Applies to: BLAZE

Issue Summary

Sometimes, connection to the Blaze Cloud server can be lost during autoscan due to an Address Resolution Protocol (ARP) table overflow. This issue typically does not occur in standard environments; it is triggered by an excessive number of devices on the network, indicating a misconfiguration in the current network setup.

To resolve this issue, segment the network to distribute devices across multiple subnets, which will alleviate ARP load and improve overall network stability. However, this article provides a temporary workaround to mitigate the issue by adjusting server settings, without requiring any changes to your current network architecture.

Resolution

The ARP cache on the Ubuntu server is exhausted due to excessive network devices or aggressive traffic, causing the server to drop incoming data.

Temporary Workaround

This is a temporary measure that only affects the current session. These settings will be reset upon system reboot.

Execute the following commands in your terminal to immediately increase the ARP cache threshold.

sudo sysctl -w net.ipv4.neigh.default.gc_thresh1=2048

sudo sysctl -w net.ipv4.neigh.default.gc_thresh2=4096

sudo sysctl -w net.ipv4.neigh.default.gc_thresh3=8192

Permanent Solution

To ensure these settings persist after a system reboot, you must append them to the system configuration file.

Run the following command to save the changes permanently.

sudo bash -c 'cat >> /etc/sysctl.conf << EOF

net.ipv4.neigh.default.gc_thresh1 = 2048

net.ipv4.neigh.default.gc_thresh2 = 4096

net.ipv4.neigh.default.gc_thresh3 = 8192

EOF'