iptables NAT转发

Last login: Sun Sep 20 23:51:55 2020 from 192.168.117.59
[root@localhost ~]#  cat /var/log/messages|grep conn   
[root@localhost ~]# dmesg | grep conntrack
[   18.842689] nf_conntrack version 0.5.0 (65536 buckets, 262144 max)
[2936843.523511] nf_conntrack version 0.5.0 (65536 buckets, 262144 max)
[root@localhost ~]# cat /proc/net/nf_conntrack | wc -l
7
[root@localhost ~]# cat /proc/net/nf_conntrack
ipv4     2 icmp     1 29 src=192.168.25.238 dst=192.168.60.15 type=8 code=0 id=1 src=192.168.60.15 dst=192.168.25.238 type=0 code=0 id=1 mark=0 secctx=system_u:object_r:unlabeled_t:s0 zone=0 use=2
ipv4     2 tcp      6 96753 ESTABLISHED src=210.22.22.134 dst=210.22.22.154 sport=31817 dport=22 src=210.22.22.154 dst=210.22.22.134 sport=22 dport=31817 [ASSURED] mark=0 secctx=system_u:object_r:unlabeled_t:s0 zone=0 use=2
ipv4     2 udp      17 25 src=192.168.8.18 dst=255.255.255.255 sport=67 dport=68 [UNREPLIED] src=255.255.255.255 dst=192.168.8.18 sport=68 dport=67 mark=0 secctx=system_u:object_r:unlabeled_t:s0 zone=0 use=2
ipv4     2 udp      17 25 src=0.0.0.0 dst=255.255.255.255 sport=68 dport=67 [UNREPLIED] src=255.255.255.255 dst=0.0.0.0 sport=67 dport=68 mark=0 secctx=system_u:object_r:unlabeled_t:s0 zone=0 use=2
ipv4     2 tcp      6 96738 ESTABLISHED src=210.22.22.134 dst=210.22.22.154 sport=31816 dport=22 src=210.22.22.154 dst=210.22.22.134 sport=22 dport=31816 [ASSURED] mark=0 secctx=system_u:object_r:unlabeled_t:s0 zone=0 use=2
ipv4     2 udp      17 16 src=192.168.117.38 dst=192.168.117.255 sport=137 dport=137 [UNREPLIED] src=192.168.117.255 dst=192.168.117.38 sport=137 dport=137 mark=0 secctx=system_u:object_r:unlabeled_t:s0 zone=0 use=2
ipv4     2 udp      17 14 src=192.168.117.23 dst=255.255.255.255 sport=64756 dport=22313 [UNREPLIED] src=255.255.255.255 dst=192.168.117.23 sport=22313 dport=64756 mark=0 secctx=system_u:object_r:unlabeled_t:s0 zone=0 use=2
ipv4     2 tcp      6 300 ESTABLISHED src=192.168.117.59 dst=192.168.117.240 sport=64629 dport=60000 src=192.168.117.240 dst=192.168.117.59 sport=60000 dport=64629 [ASSURED] mark=0 secctx=system_u:object_r:unlabeled_t:s0 zone=0 use=2
ipv4     2 udp      17 18 src=192.168.117.28 dst=192.168.117.255 sport=138 dport=138 [UNREPLIED] src=192.168.117.255 dst=192.168.117.28 sport=138 dport=138 mark=0 secctx=system_u:object_r:unlabeled_t:s0 zone=0 use=2
[root@localhost ~]# 

[root@localhost ~]# lsmod | grep nf_conntrack
nf_conntrack_ipv4     262144  4 
nf_defrag_ipv4        262144  1 nf_conntrack_ipv4
nf_conntrack          327680  6 xt_nat,nf_conntrack_ipv4,ipt_MASQUERADE,nf_nat_masquerade_ipv4,nf_nat_ipv4,nf_nat
libcrc32c             262144  3 nf_conntrack,xfs,nf_nat
[root@localhost ~]#