diff --git a/install/production-filesystem/entrypoint.d/37-host-optimization.sh b/install/production-filesystem/entrypoint.d/37-host-optimization.sh index 6cfe9b9f..4dc5d019 100644 --- a/install/production-filesystem/entrypoint.d/37-host-optimization.sh +++ b/install/production-filesystem/entrypoint.d/37-host-optimization.sh @@ -1,92 +1,30 @@ #!/bin/sh -# 37-host-optimization.sh: Apply and validate network optimizations (ARP flux fix) +# 37-host-optimization.sh: Detect ARP flux sysctl configuration. # -# This script improves detection accuracy by ensuring proper ARP behavior. -# It attempts to apply sysctl settings and warns if not possible. +# This script does not change host/kernel settings. -# --- Color Codes --- -RED=$(printf '\033[1;31m') YELLOW=$(printf '\033[1;33m') RESET=$(printf '\033[0m') -# --- Skip flag --- -if [ -n "${SKIP_OPTIMIZATIONS:-}" ]; then - exit 0 -fi - -# --- Helpers --- - -get_sysctl() { - sysctl -n "$1" 2>/dev/null || echo "unknown" -} - -set_sysctl_if_needed() { - key="$1" - expected="$2" - - current="$(get_sysctl "$key")" - - # Already correct - if [ "$current" = "$expected" ]; then - return 0 - fi - - # Try to apply - if sysctl -w "$key=$expected" >/dev/null 2>&1; then - return 0 - fi - - # Failed - return 1 -} - -# --- Apply Settings (best effort) --- - failed=0 -set_sysctl_if_needed net.ipv4.conf.all.arp_ignore 1 || failed=1 -set_sysctl_if_needed net.ipv4.conf.all.arp_announce 2 || failed=1 -set_sysctl_if_needed net.ipv4.conf.default.arp_ignore 1 || failed=1 -set_sysctl_if_needed net.ipv4.conf.default.arp_announce 2 || failed=1 +[ "$(sysctl -n net.ipv4.conf.all.arp_ignore 2>/dev/null || echo unknown)" = "1" ] || failed=1 +[ "$(sysctl -n net.ipv4.conf.all.arp_announce 2>/dev/null || echo unknown)" = "2" ] || failed=1 -# --- Validate final state --- - -all_ignore="$(get_sysctl net.ipv4.conf.all.arp_ignore)" -all_announce="$(get_sysctl net.ipv4.conf.all.arp_announce)" - -# --- Warning Output --- - -if [ "$all_ignore" != "1" ] || [ "$all_announce" != "2" ]; then +if [ "$failed" -eq 1 ]; then >&2 printf "%s" "${YELLOW}" - >&2 cat <&2 cat <<'EOF' ══════════════════════════════════════════════════════════════════════════════ -⚠️ ATTENTION: ARP flux protection not enabled. - - NetAlertX relies on ARP for device detection. Your system currently allows - ARP replies from incorrect interfaces (ARP flux), which may result in: - - • False devices being detected - • IP/MAC mismatches - • Flapping device states - • Incorrect network topology - - This is common when running in Docker or multi-interface environments. - - ────────────────────────────────────────────────────────────────────────── - Recommended fix (Docker Compose): - - sysctls: - net.ipv4.conf.all.arp_ignore: 1 - net.ipv4.conf.all.arp_announce: 2 - - ────────────────────────────────────────────────────────────────────────── - Alternatively, apply on the host: +⚠️ WARNING: ARP flux sysctls are not set. + Expected values: net.ipv4.conf.all.arp_ignore=1 net.ipv4.conf.all.arp_announce=2 - Detection accuracy may be reduced until this is configured. + Detection accuracy may be reduced until configured. + + See: https://docs.netalertx.com/docker-troubleshooting/arp-flux-sysctls/ ══════════════════════════════════════════════════════════════════════════════ EOF >&2 printf "%s" "${RESET}"