KVM Guest with NAT + Bridged networking
- by Daniel
I currently have a few KVM Guests on a dedicated server with bridged networking (this works) and i can successfully ping the outside ips i assign via ifconfig (in the guest).
However, due to the fact i only have 5 public ipv4 ip addresses, i would like to port forward services like so:
hostip:port - kvm_guest:port
UPDATE
I found out KVM comes with a "default" NAT interface, so added the virtual NIC to the Guest virsh configuration then configured it in the Guest, it has the ip address:
192.168.122.112
I can successfully ping 192.168.122.112 and access all ports on 192.168.122.112 from the KVM Host, so i tried to port forward like so:
iptables -t nat -I PREROUTING -p tcp --dport 5222 -j DNAT --to-destination 192.168.122.112:2521
iptables -I FORWARD -m state -d 192.168.122.0/24 --state NEW,RELATED,ESTABLISHED -j ACCEPT
telnet KVM_HOST_IP 5222 just hangs on "trying"
telnet 192.168.122.112 2521 works
[root@node1 ~]# tcpdump port 5222
tcpdump: WARNING: eth0: no IPv4 address assigned
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on eth0, link-type EN10MB (Ethernet), capture size 65535 bytes
23:43:47.216181 IP 1.152.245.247.51183 > null.xmpp-client: Flags [S], seq 1183303931, win 65535, options [mss 1400,nop,wscale 3,nop,nop,TS val 445777813 ecr 0,sackOK,eol], length 0
23:43:48.315747 IP 1.152.245.247.51183 > null.xmpp-client: Flags [S], seq 1183303931, win 65535, options [mss 1400,nop,wscale 3,nop,nop,TS val 445778912 ecr 0,sackOK,eol], length 0
23:43:49.415606 IP 1.152.245.247.51183 > null.xmpp-client: Flags [S], seq 1183303931, win 65535, options [mss 1400,nop,wscale 3,nop,nop,TS val 445780010 ecr 0,sackOK,eol], length 0
7 packets received by filter
0 packets dropped by kernel
[root@node1 ~]# iptables -L
Chain INPUT (policy ACCEPT)
target prot opt source destination
Chain FORWARD (policy ACCEPT)
target prot opt source destination
ACCEPT all -- anywhere 192.168.122.0/24 state NEW,RELATED,ESTABLISHED
Chain OUTPUT (policy ACCEPT)
target prot opt source destination
All help is appreciated.
Thanks.
