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fix nat table by getting the fitting device for an address #9552

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fix nat table by getting the fitting device for an address #9552

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97f2828
get fitting device for address
DaanHoogland Aug 20, 2024
20c4e4b
add nat rule whether it is source-nat or not
DaanHoogland Aug 23, 2024
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9 changes: 3 additions & 6 deletions systemvm/debian/opt/cloud/bin/cs/CsAddress.py
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Original file line number Diff line number Diff line change
Expand Up @@ -554,7 +554,7 @@ def fw_vpcrouter(self):
if self.address["source_nat"]:
self.fw.append(["nat", "front",
"-A POSTROUTING -o %s -j SNAT --to-source %s" %
(self.dev, self.address['public_ip'])])
(self.address['device'], self.address['public_ip'])])
if self.get_gateway() == self.get_ip_address():
for inf, addresses in self.config.address().dbag.iteritems():
if not inf.startswith("eth"):
Expand Down Expand Up @@ -693,11 +693,8 @@ def post_config_change(self, method):
vpccidr = cmdline.get_vpccidr()
self.fw.append(
["filter", 3, "-A FORWARD -s %s ! -d %s -j ACCEPT" % (vpccidr, vpccidr)])
self.fw.append(
["nat", "", "-A POSTROUTING -j SNAT -o %s --to-source %s" % (self.dev, self.address['public_ip'])])
elif cmdline.get_source_nat_ip() and not self.is_private_gateway():
self.fw.append(
["nat", "", "-A POSTROUTING -j SNAT -o %s --to-source %s" % (self.dev, cmdline.get_source_nat_ip())])
self.fw.append(
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@weizhouapache weizhouapache Aug 26, 2024

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if there are multiple public ips (in multiple ranges), will there be same amount of rules ?

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@DaanHoogland DaanHoogland Aug 26, 2024

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I am not sure I understand the question. I checked this in a lab env and the resulting nat table was exactly as described in the issue, with only the last line being different. Ar you considdering another configuration here @weizhouapache ?

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@weizhouapache weizhouapache Aug 26, 2024

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for each public ip (and private gateway), there will be a rule below, right ?

-A POSTROUTING -j SNAT -o ethX --to-source xx.yy.zz.xx

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@weizhouapache weizhouapache Sep 20, 2024

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@DaanHoogland
to be clear, we need a rule for each public NIC, for example

-A POSTROUTING -j SNAT -o eth1 --to-source <source nat IP>    # this is for source nat NIC
-A POSTROUTING -j SNAT -o eth5 --to-source <first public IP on eth5>    # this is for additional public NIC

If I understand correctly, for the current changes , the rules are for example,

-A POSTROUTING -j SNAT -o eth1 --to-source <source nat IP>    # this is for source nat NIC
-A POSTROUTING -j SNAT -o eth1 --to-source <second IP on source nat NIC>    # this is for source nat NIC
-A POSTROUTING -j SNAT -o eth1 --to-source <third IP on source nat NIC>    # this is for source nat NIC

-A POSTROUTING -j SNAT -o eth5 --to-source <first public IP on eth5>    # this is for additional public NIC
-A POSTROUTING -j SNAT -o eth5 --to-source <second public IP on eth5>    # this is for additional public NIC
-A POSTROUTING -j SNAT -o eth5 --to-source <third public IP on eth5>    # this is for additional public NIC

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@DaanHoogland DaanHoogland Sep 20, 2024

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I'll verify that. Do you happen to know what condition to test for? I don't think the self.address object contains information on whether it is the first IP, does it?

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@weizhouapache weizhouapache Sep 20, 2024

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I think the original issue does not exist in our lab (I can verify with infra).

we can only verify the iptables rules in the VR

  • create 2 public ip ranges with different vlan
  • acquire 3 public ips on each public ip and use them for static/pf/lb

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@weizhouapache weizhouapache Sep 20, 2024

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I don't think the self.address object contains information on whether it is the first IP, does it?

it does, but I am not sure if it is 100% correct.

image

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@DaanHoogland DaanHoogland Sep 20, 2024

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ok, I'll give it a try

["nat", "", "-A POSTROUTING -j SNAT -o %s --to-source %s" % (self.dev, self.address['public_ip'])])

def list(self):
self.iplist = {}
Expand Down