vim /etc/sysctl.conf
net.ipv4.neigh.default.gc_stale_time = 120
# see details in https://help.aliyun.com/knowledge_detail/39428.html
net.ipv4.conf.all.rp_filter = 0
net.ipv4.conf.default.rp_filter = 0
net.ipv4.conf.default.arp_announce = 2
net.ipv4.conf.lo.arp_announce = 2
net.ipv4.conf.all.arp_announce = 2
# see details in https://help.aliyun.com/knowledge_detail/41334.html
net.ipv4.tcp_max_tw_buckets = 256000
net.ipv4.tcp_syncookies = 1
net.ipv4.tcp_max_syn_backlog = 256000
net.ipv4.tcp_synack_retries = 2
net.ipv4.tcp_slow_start_after_idle = 0
net.ipv4.tcp_timestamps = 1
net.ipv4.tcp_tw_reuse = 1
net.ipv4.tcp_fin_timeout= 5
#################修改内核limit########################
cat /etc/security/limits.d/20-nproc.conf
# Default limit for number of user's processes to prevent
# accidental fork bombs.
# See rhbz #432903 for reasoning.
* soft nproc 102400 #修改进程
root soft nproc unlimited