kernel.sysrq = 1
kernel.dmesg_restrict = 0
kernel.yama.ptrace_scope = 0
kernel.perf_event_paranoid = -1
net.core.netdev_max_backlog = 16384
net.core.somaxconn = 8192
net.ipv4.tcp_fastopen = 3
net.ipv4.tcp_max_syn_backlog = 8192
net.ipv4.tcp_max_tw_buckets = 2000000
net.ipv4.tcp_tw_reuse = 1
net.ipv4.tcp_fin_timeout = 10
net.ipv4.tcp_slow_start_after_idle = 0
net.ipv4.tcp_keepalive_time = 60
net.ipv4.tcp_keepalive_intvl = 10
net.ipv4.tcp_keepalive_probes = 6
net.ipv4.tcp_mtu_probing = 1
net.core.default_qdisc = cake
net.ipv4.tcp_congestion_control = bbr
vm.vfs_cache_pressure = 50

# Network hardening
net.ipv4.conf.all.rp_filter = 2
net.ipv4.conf.default.rp_filter = 2
net.ipv4.conf.all.accept_redirects = 0
net.ipv4.conf.default.accept_redirects = 0
net.ipv6.conf.all.accept_redirects = 0
net.ipv6.conf.default.accept_redirects = 0
net.ipv4.conf.all.send_redirects = 0
net.ipv4.conf.default.send_redirects = 0
net.ipv4.conf.all.accept_source_route = 0
net.ipv6.conf.all.accept_source_route = 0
net.ipv4.conf.all.log_martians = 1

# IP forwarding for NAT bridges (libvirt's virbr0, waydroid's waydroid0).
# libvirtd and waydroid both rely on the host routing between their bridge
# and the upstream NIC; without this they get no internet.
net.ipv4.ip_forward = 1