Hi everybody,I have a problem with VS using IPv6 and Pool, Node IPv4.My config :- VS type is Performance Layer 4; - Source Address Translation: none- Address Translation: enable- Port Translation: enable-NAT64: enableWith same Pool member for VS using ipv4 then VS working, but when I connection to VS ipv6 then have error : ERR_CONNECTION_REFUSEDHave any ideal for this problem? Thanks

This problem has resolved. TCP conection from F5 to internal over 64k connection, so a new tcp session is started with the same ports => tcp connection reset. Need SNAT with other self ip connection to internal.

F5 Bigip LTM NAT64 config

31 Replies

mihaic
MVP
Nov 22, 2022
I think an IPv6 VIP and a pool with IPv4 and Source NAT enabled is enough to make it work.
- longnv
  Cirrus
  Nov 22, 2022
  I tried Source Address Translation with 2 option none and auto map, but VS not working. Ping VS is ok but service HTTPS of VS not work
mihaic
MVP
Nov 22, 2022
disable NAT64 , and have Source NAT on automap.
- longnv
  Cirrus
  Nov 22, 2022
  I tried it, but VS not working still
mihaic
MVP
Nov 22, 2022
Maybe i did not understand the problem.
You have an IPv6 VIP , going to a pool of nodes with IPv4. And it is not working
But when the VIP has IPv4 , going to the same pool of IPv4 , it is working.
- longnv
  Cirrus
  Nov 22, 2022
  Yes, I'm trying config VS ipv6 for node ipv4
mihaic
MVP
Nov 22, 2022
please share the config of the vip,irule if you have and the pool
- longnv
  Cirrus
  Nov 22, 2022
  Send to you my VS config below:
  ltm virtual VS_IPV6_p443 {
  destination 2001:df1:1f40::11.https
  ip-protocol tcp
  pool P_PORTAL_443
  profiles {
  fastL4 { }
  }
  source-address-translation {
  type automap
  }
  translate-address enabled
  translate-port enabled
  vs-index 808
  
  ltm virtual VS_IPV4_p443 {
  destination 103.57.112.17:https
  ip-protocol tcp
  mask 255.255.255.255
  pool P_PORTAL_443
  profiles {
  tcp { }
  }
  source 0.0.0.0/0
  translate-address enabled
  translate-port enabled
  vs-index 802
  }
mihaic
MVP
Nov 22, 2022
Did you try to use tcp profile instead of fastl4 on the IPv6 vip?
longnv
Cirrus
Nov 22, 2022
I tried it
mihaic
MVP
Nov 22, 2022
I know it might sound stupid, but when you test with IPv6, are you sure you are accessing the vip using IPv6 address?
Your client needs to have an IPv6.
can you share the logs and , or have a tcpdump?
- longnv
  Cirrus
  Nov 22, 2022
  Send to you pcap file, i run tcpdump on f5
  portal-angiang.zip1 KB
mihaic
MVP
Nov 22, 2022
you used this command:
tcpdump -nni VLAN_VNNIC2_CMC_NETNAM_2022 -w /var/tmp/portal-angiang.pcap src host 2405:4803:fe2a:f320:ddca:770d:da6d:d54d
This shows only one way traffic. from source 2405:4803:fe2a:f320:ddca:770d:da6d:d54d
That's why we don't see any reply
You should use something like this for client side:
tcpdump -nni 0.0:n -s0 host 2405:4803:fe2a:f320:ddca:770d:da6d:d54d
Also it might be interesting to see the server side also.
- longnv
  Cirrus
  Nov 22, 2022
  My client's ip is 2401:d800:5357:50b6:98:f028:b92e:3d44
  20:23:18.757233 IP6 2401:d800:5357:50b6:98:f028:b92e:3d44.43366 > 2001:df1:1f40::11.443: Flags [S], seq 1503358393, win 65535, options [mss 1360,sackOK,TS val 19118655 ecr 0,nop,wscale 8], length 0 in slot1/tmm2 lis=
  20:23:18.757248 IP6 2001:df1:1f40::11.443 > 2401:d800:5357:50b6:98:f028:b92e:3d44.43366: Flags [R.], seq 0, ack 1503358394, win 0, length 0 out slot1/tmm2 lis=/Common/VS_IPV6_p443
  20:23:18.798124 IP6 2401:d800:5357:50b6:98:f028:b92e:3d44.43368 > 2001:df1:1f40::11.443: Flags [S], seq 990884170, win 65535, options [mss 1360,sackOK,TS val 19118666 ecr 0,nop,wscale 8], length 0 in slot1/tmm1 lis=
  20:23:18.798140 IP6 2001:df1:1f40::11.443 > 2401:d800:5357:50b6:98:f028:b92e:3d44.43368: Flags [R.], seq 0, ack 990884171, win 0, length 0 out slot1/tmm1 lis=/Common/VS_IPV6_p443
  20:23:18.813194 IP6 2401:d800:5357:50b6:98:f028:b92e:3d44.43370 > 2001:df1:1f40::11.443: Flags [S], seq 2676317898, win 65535, options [mss 1360,sackOK,TS val 19118666 ecr 0,nop,wscale 8], length 0 in slot1/tmm3 lis=
  20:23:18.813221 IP6 2001:df1:1f40::11.443 > 2401:d800:5357:50b6:98:f028:b92e:3d44.43370: Flags [R.], seq 0, ack 2676317899, win 0, length 0 out slot1/tmm3 lis=/Common/VS_IPV6_p443
  20:23:21.618714 IP6 2401:d800:5357:50b6:98:f028:b92e:3d44.43372 > 2001:df1:1f40::11.443: Flags [S], seq 3056621442, win 65535, options [mss 1360,sackOK,TS val 19119370 ecr 0,nop,wscale 8], length 0 in slot1/tmm2 lis=
  20:23:21.618735 IP6 2001:df1:1f40::11.443 > 2401:d800:5357:50b6:98:f028:b92e:3d44.43372: Flags [R.], seq 0, ack 3056621443, win 0, length 0 out slot1/tmm2 lis=/Common/VS_IPV6_p443
  20:23:21.637323 IP6 2401:d800:5357:50b6:98:f028:b92e:3d44.43374 > 2001:df1:1f40::11.443: Flags [S], seq 307561307, win 65535, options [mss 1360,sackOK,TS val 19119376 ecr 0,nop,wscale 8], length 0 in slot1/tmm0 lis=
  20:23:21.637338 IP6 2001:df1:1f40::11.443 > 2401:d800:5357:50b6:98:f028:b92e:3d44.43374: Flags [R.], seq 0, ack 307561308, win 0, length 0 out slot1/tmm0 lis=/Common/VS_IPV6_p443
  20:23:26.425240 IP6 2401:d800:5357:50b6:98:f028:b92e:3d44.43376 > 2001:df1:1f40::11.443: Flags [S], seq 2494555277, win 65535, options [mss 1360,sackOK,TS val 19120571 ecr 0,nop,wscale 8], length 0 in slot1/tmm3 lis=
  20:23:26.425264 IP6 2001:df1:1f40::11.443 > 2401:d800:5357:50b6:98:f028:b92e:3d44.43376: Flags [R.], seq 0, ack 2494555278, win 0, length 0 out slot1/tmm3 lis=/Common/VS_IPV6_p443
  20:23:26.439167 IP6 2401:d800:5357:50b6:98:f028:b92e:3d44.43378 > 2001:df1:1f40::11.443: Flags [S], seq 409910347, win 65535, options [mss 1360,sackOK,TS val 19120578 ecr 0,nop,wscale 8], length 0 in slot1/tmm1 lis=
  20:23:26.439181 IP6 2001:df1:1f40::11.443 > 2401:d800:5357:50b6:98:f028:b92e:3d44.43378: Flags [R.], seq 0, ack 409910348, win 0, length 0 out slot1/tmm1 lis=/Common/VS_IPV6_p443
mihaic
MVP
Nov 22, 2022
something like this will capture both the client and server side:
tcpdump -ni 0.0:nnnp -s0 -c 100000 -w /var/tmp/capture.pcap host 2001:df1:1f40::11
https://support.f5.com/csp/article/K13637
- longnv
  Cirrus
  Nov 22, 2022
  My ipv6 to test is 2401:d800:5357:50b6:98:f028:b92e:3d44
  20:23:18.757233 IP6 2401:d800:5357:50b6:98:f028:b92e:3d44.43366 > 2001:df1:1f40::11.443: Flags [S], seq 1503358393, win 65535, options [mss 1360,sackOK,TS val 19118655 ecr 0,nop,wscale 8], length 0 in slot1/tmm2 lis=
  20:23:18.757248 IP6 2001:df1:1f40::11.443 > 2401:d800:5357:50b6:98:f028:b92e:3d44.43366: Flags [R.], seq 0, ack 1503358394, win 0, length 0 out slot1/tmm2 lis=/Common/VS_IPV6_p443
  20:23:18.798124 IP6 2401:d800:5357:50b6:98:f028:b92e:3d44.43368 > 2001:df1:1f40::11.443: Flags [S], seq 990884170, win 65535, options [mss 1360,sackOK,TS val 19118666 ecr 0,nop,wscale 8], length 0 in slot1/tmm1 lis=
  20:23:18.798140 IP6 2001:df1:1f40::11.443 > 2401:d800:5357:50b6:98:f028:b92e:3d44.43368: Flags [R.], seq 0, ack 990884171, win 0, length 0 out slot1/tmm1 lis=/Common/VS_IPV6_p443
  20:23:18.813194 IP6 2401:d800:5357:50b6:98:f028:b92e:3d44.43370 > 2001:df1:1f40::11.443: Flags [S], seq 2676317898, win 65535, options [mss 1360,sackOK,TS val 19118666 ecr 0,nop,wscale 8], length 0 in slot1/tmm3 lis=
  - mihaic
    MVP
    Nov 22, 2022
    it seems the F5 sends you back a Reset every time you send a SYN.
    Here is an article with possible reasons why an F5 sens Reset:
    https://support.f5.com/csp/article/K9812
    "You can associate the FastL4 profile with the following virtual types:
    Performance (Layer 4)
    Forwarding (Layer 2)
    Forwarding (IP)
    Internal"
    So try changing the VIP from standard to performance (Layer4).
longnv
Cirrus
Nov 22, 2022
My client ip to test is 2401:d800:5357:50b6:98:f028:b92e:3d44
20:23:18.757233 IP6 2401:d800:5357:50b6:98:f028:b92e:3d44.43366 > 2001:df1:1f40::11.443: Flags [S], seq 1503358393, win 65535, options [mss 1360,sackOK,TS val 19118655 ecr 0,nop,wscale 8], length 0 in slot1/tmm2 lis=
20:23:18.757248 IP6 2001:df1:1f40::11.443 > 2401:d800:5357:50b6:98:f028:b92e:3d44.43366: Flags [R.], seq 0, ack 1503358394, win 0, length 0 out slot1/tmm2 lis=/Common/VS_IPV6_p443
20:23:18.798124 IP6 2401:d800:5357:50b6:98:f028:b92e:3d44.43368 > 2001:df1:1f40::11.443: Flags [S], seq 990884170, win 65535, options [mss 1360,sackOK,TS val 19118666 ecr 0,nop,wscale 8], length 0 in slot1/tmm1 lis=
20:23:18.798140 IP6 2001:df1:1f40::11.443 > 2401:d800:5357:50b6:98:f028:b92e:3d44.43368: Flags [R.], seq 0, ack 990884171, win 0, length 0 out slot1/tmm1 lis=/Common/VS_IPV6_p443
20:23:18.813194 IP6 2401:d800:5357:50b6:98:f028:b92e:3d44.43370 > 2001:df1:1f40::11.443: Flags [S], seq 2676317898, win 65535, options [mss 1360,sackOK,TS val 19118666 ecr 0,nop,wscale 8], length 0 in slot1/tmm3 lis=
20:23:18.813221 IP6 2001:df1:1f40::11.443 > 2401:d800:5357:50b6:98:f028:b92e:3d44.43370: Flags [R.], seq 0, ack 2676317899, win 0, length 0 out slot1/tmm3 lis=/Common/VS_IPV6_p443
20:23:21.618714 IP6 2401:d800:5357:50b6:98:f028:b92e:3d44.43372 > 2001:df1:1f40::11.443: Flags [S], seq 3056621442, win 65535, options [mss 1360,sackOK,TS val 19119370 ecr 0,nop,wscale 8], length 0 in slot1/tmm2 lis=
20:23:21.618735 IP6 2001:df1:1f40::11.443 > 2401:d800:5357:50b6:98:f028:b92e:3d44.43372: Flags [R.], seq 0, ack 3056621443, win 0, length 0 out slot1/tmm2 lis=/Common/VS_IPV6_p443
20:23:21.637323 IP6 2401:d800:5357:50b6:98:f028:b92e:3d44.43374 > 2001:df1:1f40::11.443: Flags [S], seq 307561307, win 65535, options [mss 1360,sackOK,TS val 19119376 ecr 0,nop,wscale 8], length 0 in slot1/tmm0 lis=
20:23:21.637338 IP6 2001:df1:1f40::11.443 > 2401:d800:5357:50b6:98:f028:b92e:3d44.43374: Flags [R.], seq 0, ack 307561308, win 0, length 0 out slot1/tmm0 lis=/Common/VS_IPV6_p443
20:23:26.425240 IP6 2401:d800:5357:50b6:98:f028:b92e:3d44.43376 > 2001:df1:1f40::11.443: Flags [S], seq 2494555277, win 65535, options [mss 1360,sackOK,TS val 19120571 ecr 0,nop,wscale 8], length 0 in slot1/tmm3 lis=
20:23:26.425264 IP6 2001:df1:1f40::11.443 > 2401:d800:5357:50b6:98:f028:b92e:3d44.43376: Flags [R.], seq 0, ack 2494555278, win 0, length 0 out slot1/tmm3 lis=/Common/VS_IPV6_p443
20:23:26.439167 IP6 2401:d800:5357:50b6:98:f028:b92e:3d44.43378 > 2001:df1:1f40::11.443: Flags [S], seq 409910347, win 65535, options [mss 1360,sackOK,TS val 19120578 ecr 0,nop,wscale 8], length 0 in slot1/tmm1 lis=
20:23:26.439181 IP6 2001:df1:1f40::11.443 > 2401:d800:5357:50b6:98:f028:b92e:3d44.43378: Flags [R.], seq 0, ack 409910348, win 0, length 0 out slot1/tmm1 lis=/Common/VS_IPV6_p443

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