Virtual IP alias as gateway for a subnet
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The only way that can happen on Automatic Outbound NAT is if the firewall doesn't know there is a WAN, meaning Interfaces > WAN has no gateway selected from the drop-down on that page.
Seems there is another way…. see attached WAN does have a gateway selected.
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Ah, well there is one more I forgot - if the LAN interface does have a gateway set, it would think that the LAN is a WAN so it wouldn't do NAT.
You don't need nor want to have a gateway set on the LAN interface, and if you have a gateway defined that is actually your LAN IP, remove it.
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Ah, well there is one more I forgot - if the LAN interface does have a gateway set, it would think that the LAN is a WAN so it wouldn't do NAT.
Makes total sense, it did have a gateway set.
You don't need nor want to have a gateway set on the LAN interface, and if you have a gateway defined that is actually your LAN IP, remove it.
Sure, sure. Selected 'none' as gateway for LAN interface, reset states, rebooted pfsense and …. (still rebooting) .... nope! No luck, no echo reply from 8.8.8.8 to 10.0.0.8. Partial success though: my workstation on 192.168.0.0/24 does ping 8.8.8.8 and am using it now to post to the forum :)
What the heck! Let me reboot 10.0.0.8 and see what happens, it is a Win XP anyway and my workstation is linux. Rebooted and no luck yet. Dont' forget 10.0.0.8 uses 10.0.0.5 as default gateway, which is a VIP Alias on pfsense.
States and packet capture on WAN interface attached.
16:34:10.530106 IP 10.0.0.8 > 8.8.8.8: ICMP echo request, id 512, seq 9216, length 40 16:34:16.030458 IP 10.0.0.8 > 8.8.8.8: ICMP echo request, id 512, seq 9472, length 40 16:34:21.532543 IP 10.0.0.8 > 8.8.8.8: ICMP echo request, id 512, seq 9728, length 40
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Forgot to mention: also deselected a gateway for ADSL interface, just to be sure.
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So it's still not getting NAT, do you see nat rules in /tmp/rules.debug now?
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Forgot to mention: also deselected a gateway for ADSL interface, just to be sure.
Why?
WANs must have a gateway set.
LANs must not have a gateway set.Otherwise automatic outbound NAT will not work.
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So it's still not getting NAT, do you see nat rules in /tmp/rules.debug now?
Not yet (oops, regarding 10.0.0.0/24):
#System aliases loopback = "{ lo0 }" WAN = "{ xl0 }" LAN = "{ bge1 }" ADSL = "{ bge0 }" #SSH Lockout Table table <sshlockout>persist table <webconfiguratorlockout>persist #Snort tables table <snort2c>table <virusprot># User Aliases table <lanvisitantes>{ 10.0.0.0/24 } LanVisitantes = "<lanvisitantes>" # Gateways GWGWADSL = " route-to ( bge0 192.168.1.100 ) " GWGWWAN = " route-to ( xl0 177.135.88.153 ) " GWGWLANNS100 = " route-to ( bge1 192.168.0.254 ) " GWGWLANRV042 = " route-to ( bge1 192.168.0.251 ) " GWGW_Group = " route-to { ( bge0 192.168.1.100 ) } " set loginterface bge1 set optimization normal set limit states 96000 set limit src-nodes 96000 set skip on pfsync0 scrub in on $WAN all fragment reassemble scrub in on $LAN all fragment reassemble scrub in on $ADSL all fragment reassemble no nat proto carp no rdr proto carp nat-anchor "natearly/*" nat-anchor "natrules/*" # Outbound NAT rules # Subnets to NAT tonatsubnets = "{ 192.168.0.0/24 192.168.1.0/24 127.0.0.0/8 }" nat on $WAN from $tonatsubnets port 500 to any port 500 -> 177.135.88.154/32 port 500 nat on $WAN from $tonatsubnets to any -> 177.135.88.154/32 port 1024:65535 # Load balancing anchor rdr-anchor "relayd/*" # TFTP proxy rdr-anchor "tftp-proxy/*" table <negate_networks>{ 177.135.88.152/29 192.168.0.0/24 192.168.1.0/24 } # UPnPd rdr anchor rdr-anchor "miniupnpd" anchor "relayd/*" #--------------------------------------------------------------------------- # default deny rules #--------------------------------------------------------------------------- block in log all label "Default deny rule" block out log all label "Default deny rule" # We use the mighty pf, we cannot be fooled. block quick proto { tcp, udp } from any port = 0 to any block quick proto { tcp, udp } from any to any port = 0 # Block all IPv6 block in quick inet6 all block out quick inet6 all # Snort package block quick from <snort2c>to any label "Block snort2c hosts" block quick from any to <snort2c>label "Block snort2c hosts" block in log quick proto carp from (self) to any pass quick proto carp pass quick proto pfsync # SSH lockout block in log quick proto tcp from <sshlockout>to any port 22 label "sshlockout" # webConfigurator lockout block in log quick proto tcp from <webconfiguratorlockout>to any port 80 label "webConfiguratorlockout" block in quick from <virusprot>to any label "virusprot overload table" antispoof for xl0 antispoof for bge1 antispoof for bge0 # loopback pass in on $loopback all label "pass loopback" pass out on $loopback all label "pass loopback" # let out anything from the firewall host itself and decrypted IPsec traffic pass out all keep state allow-opts label "let out anything from firewall host itself" pass out route-to ( xl0 177.135.88.153 ) from 177.135.88.154 to !177.135.88.152/29 keep state allow-opts label "let out anything from firewall host itself" # make sure the user cannot lock himself out of the webConfigurator or SSH pass in quick on bge1 proto tcp from any to (bge1) port { 80 22 } keep state label "anti-lockout rule" # User-defined rules follow anchor "userrules/*" pass on { xl0 bge1 bge0 } inet proto icmp from any to any keep state label "USER_RULE" pass in quick on $WAN reply-to ( xl0 177.135.88.153 ) inet proto icmp from any to any keep state label "USER_RULE" pass in quick on $LAN inet proto icmp from any to any keep state label "USER_RULE" pass in quick on $LAN from 192.168.0.0/24 to any keep state label "USER_RULE: Default allow LAN to any rule" pass in quick on $LAN from $LanVisitantes to any keep state label "USER_RULE" pass in quick on $LAN from any to $LanVisitantes keep state label "USER_RULE" pass in quick on $ADSL inet proto icmp from any to any keep state label "USER_RULE" # VPN Rules anchor "tftp-proxy/*"</virusprot></webconfiguratorlockout></sshlockout></snort2c></snort2c></negate_networks></lanvisitantes></lanvisitantes></virusprot></snort2c></webconfiguratorlockout></sshlockout>So, I erased the VIP and created again, without a gateway on LAN interface, reset states, and now 10.0.0.8 cannot even ping 10.0.0.5. Packets and state table:
16:45:12.039107 ARP, Request who-has 10.0.0.8 tell 10.0.0.5, length 28 16:45:17.539196 ARP, Request who-has 10.0.0.8 tell 10.0.0.5, length 28
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Closer..
# Subnets to NAT tonatsubnets = "{ 192.168.0.0/24 192.168.1.0/24 127.0.0.0/8 }"It is getting your other subnets but not the 10.x.x.x one.
Make sure the IP alias VIP has the proper subnet mask set (not /32).
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It is getting your other subnets but not the 10.x.x.x one.
Make sure the IP alias VIP has the proper subnet mask set (not /32)./24
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And that IP alias is on the correct interface? (LAN)
Check Diagnostics > Routes, paste the output here, it might give some more clues.
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OK that all looks good now - and if you check /tmp/rules.debug and look for tonatsubnets - the 10.x.x.x network still doesn't show up?
If not, then you probably will need to go to outbound NAT, delete any rules there, and switch to manual outbound NAT once more. Then add a rule for 10.x.x.x.
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OK that all looks good now - and if you check /tmp/rules.debug and look for tonatsubnets - the 10.x.x.x network still doesn't show up?
Nope:
# Subnets to NAT tonatsubnets = "{ 192.168.0.0/24 192.168.1.0/24 127.0.0.0/8 }" nat on $WAN from $tonatsubnets port 500 to any port 500 -> x.x.x.154/32 port 500 nat on $WAN from $tonatsubnets to any -> x.x.x.154/32 port 1024:65535If not, then you probably will need to go to outbound NAT, delete any rules there, and switch to manual outbound NAT once more. Then add a rule for 10.x.x.x.
Why can't that be automatic? Why life can't be easy? Why there's no Santa Claus?
Did not delete existing rules, they look good for me. I just added new NAT rule, reset states, and this time got luck, 10.0.0.8 now pings 8.8.8.8.Now the questions:
Is that a bug or feature?
If not a feature, where can I request it?This box will replace an old Netscreen, 1:1 NATing a bunch of servers, responsible for our internet presence, connect two remote offices, provide IPsec VPN for mobile warriors, and some more I don't remember now.
Will leave on vacation now and get back on january 7 to finish this. Happy holidays, merry Christmas, happy end-of-the-world, happy new year, and many thanks for your almost-chat support. I was almost ditching pfsense.
Best regards,
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Marcio Merlone -
I had thought it was automatic, but it's apparently not (at least on the version you're using, I don't know about 2.1)
Using multiple subnets on a single interface in that was is still mostly an edge case. Most people put distinct subnets on separate VLANs or interfaces.
