catch iptables logs from container to host
I'm trying to catch the logs generated by iptables running inside a container.
Since LOG support is disabled for container (see here), I'm trying to set the iptables log rules in the host.
I'm testing it with a rule (on the host) that catches a SYN scan from NMap (*1).
So the idea is to set iptables rules on host to log scans performed against a container (named c_victim
), which is using a virtual bridged interface br-a1b2c3
(*2).
I've tried different rules similar to:
# iptables -I FORWARD -m physdev --physdev-out veth144i0 --physdev-is-bridged -j LOG --log-prefix "[fw::test]"
where veth144i0
is the virtual ethernet interface associated to br-a1b2c3
(*3). I got this rule from here.
None of the rules I tried generated logs in my host after checking with:
$ journalctl -b | grep "[fw.*]"
Any ideas on how to set the iptables rule in (*1) for a container??
(*1): Just to make sure that the rule works, I tested it in my host:
# iptables -I INPUT -p tcp -m multiport --dports 23,79 --tcp-flags ALL SYN -m limit --limit 3/m --limit-burst 5 -j LOG --log-prefix "[fw::syn-scan] "
then scanned the host from a container with:
root@887952fed115# nmap -sS 192.168.0.14
and then checked the logs with:
$ journalctl -b | grep "[fw.*]"
where the logs of the scan appear ok.
(*2): I know this because I checked using a combination of these commands:
$ docker container inspect c_victim | grep NetworkID
$ docker network ls
$ ifconfig -a
(*3): I checked this by looking at the symlinks:
ls -l /sys/devices/virtual/net/veth*/master
As exploratory checks, I also set the rules (in host always):
# iptables -I FORWARD -i br-a1b2c3 -j LOG --log-prefix "[fw::test-in]"
# iptables -I FORWARD -o br-a1b2c3 -j LOG --log-prefix "[fw::test-out]"
to see what happens, and this is what I get:
- no logs are generated if I scan the container from the host.
- only the first one generates logs in my journalctl if I scan the host from the container
c_victim
.
docker networking iptables virtual-network
add a comment |
I'm trying to catch the logs generated by iptables running inside a container.
Since LOG support is disabled for container (see here), I'm trying to set the iptables log rules in the host.
I'm testing it with a rule (on the host) that catches a SYN scan from NMap (*1).
So the idea is to set iptables rules on host to log scans performed against a container (named c_victim
), which is using a virtual bridged interface br-a1b2c3
(*2).
I've tried different rules similar to:
# iptables -I FORWARD -m physdev --physdev-out veth144i0 --physdev-is-bridged -j LOG --log-prefix "[fw::test]"
where veth144i0
is the virtual ethernet interface associated to br-a1b2c3
(*3). I got this rule from here.
None of the rules I tried generated logs in my host after checking with:
$ journalctl -b | grep "[fw.*]"
Any ideas on how to set the iptables rule in (*1) for a container??
(*1): Just to make sure that the rule works, I tested it in my host:
# iptables -I INPUT -p tcp -m multiport --dports 23,79 --tcp-flags ALL SYN -m limit --limit 3/m --limit-burst 5 -j LOG --log-prefix "[fw::syn-scan] "
then scanned the host from a container with:
root@887952fed115# nmap -sS 192.168.0.14
and then checked the logs with:
$ journalctl -b | grep "[fw.*]"
where the logs of the scan appear ok.
(*2): I know this because I checked using a combination of these commands:
$ docker container inspect c_victim | grep NetworkID
$ docker network ls
$ ifconfig -a
(*3): I checked this by looking at the symlinks:
ls -l /sys/devices/virtual/net/veth*/master
As exploratory checks, I also set the rules (in host always):
# iptables -I FORWARD -i br-a1b2c3 -j LOG --log-prefix "[fw::test-in]"
# iptables -I FORWARD -o br-a1b2c3 -j LOG --log-prefix "[fw::test-out]"
to see what happens, and this is what I get:
- no logs are generated if I scan the container from the host.
- only the first one generates logs in my journalctl if I scan the host from the container
c_victim
.
docker networking iptables virtual-network
add a comment |
I'm trying to catch the logs generated by iptables running inside a container.
Since LOG support is disabled for container (see here), I'm trying to set the iptables log rules in the host.
I'm testing it with a rule (on the host) that catches a SYN scan from NMap (*1).
So the idea is to set iptables rules on host to log scans performed against a container (named c_victim
), which is using a virtual bridged interface br-a1b2c3
(*2).
I've tried different rules similar to:
# iptables -I FORWARD -m physdev --physdev-out veth144i0 --physdev-is-bridged -j LOG --log-prefix "[fw::test]"
where veth144i0
is the virtual ethernet interface associated to br-a1b2c3
(*3). I got this rule from here.
None of the rules I tried generated logs in my host after checking with:
$ journalctl -b | grep "[fw.*]"
Any ideas on how to set the iptables rule in (*1) for a container??
(*1): Just to make sure that the rule works, I tested it in my host:
# iptables -I INPUT -p tcp -m multiport --dports 23,79 --tcp-flags ALL SYN -m limit --limit 3/m --limit-burst 5 -j LOG --log-prefix "[fw::syn-scan] "
then scanned the host from a container with:
root@887952fed115# nmap -sS 192.168.0.14
and then checked the logs with:
$ journalctl -b | grep "[fw.*]"
where the logs of the scan appear ok.
(*2): I know this because I checked using a combination of these commands:
$ docker container inspect c_victim | grep NetworkID
$ docker network ls
$ ifconfig -a
(*3): I checked this by looking at the symlinks:
ls -l /sys/devices/virtual/net/veth*/master
As exploratory checks, I also set the rules (in host always):
# iptables -I FORWARD -i br-a1b2c3 -j LOG --log-prefix "[fw::test-in]"
# iptables -I FORWARD -o br-a1b2c3 -j LOG --log-prefix "[fw::test-out]"
to see what happens, and this is what I get:
- no logs are generated if I scan the container from the host.
- only the first one generates logs in my journalctl if I scan the host from the container
c_victim
.
docker networking iptables virtual-network
I'm trying to catch the logs generated by iptables running inside a container.
Since LOG support is disabled for container (see here), I'm trying to set the iptables log rules in the host.
I'm testing it with a rule (on the host) that catches a SYN scan from NMap (*1).
So the idea is to set iptables rules on host to log scans performed against a container (named c_victim
), which is using a virtual bridged interface br-a1b2c3
(*2).
I've tried different rules similar to:
# iptables -I FORWARD -m physdev --physdev-out veth144i0 --physdev-is-bridged -j LOG --log-prefix "[fw::test]"
where veth144i0
is the virtual ethernet interface associated to br-a1b2c3
(*3). I got this rule from here.
None of the rules I tried generated logs in my host after checking with:
$ journalctl -b | grep "[fw.*]"
Any ideas on how to set the iptables rule in (*1) for a container??
(*1): Just to make sure that the rule works, I tested it in my host:
# iptables -I INPUT -p tcp -m multiport --dports 23,79 --tcp-flags ALL SYN -m limit --limit 3/m --limit-burst 5 -j LOG --log-prefix "[fw::syn-scan] "
then scanned the host from a container with:
root@887952fed115# nmap -sS 192.168.0.14
and then checked the logs with:
$ journalctl -b | grep "[fw.*]"
where the logs of the scan appear ok.
(*2): I know this because I checked using a combination of these commands:
$ docker container inspect c_victim | grep NetworkID
$ docker network ls
$ ifconfig -a
(*3): I checked this by looking at the symlinks:
ls -l /sys/devices/virtual/net/veth*/master
As exploratory checks, I also set the rules (in host always):
# iptables -I FORWARD -i br-a1b2c3 -j LOG --log-prefix "[fw::test-in]"
# iptables -I FORWARD -o br-a1b2c3 -j LOG --log-prefix "[fw::test-out]"
to see what happens, and this is what I get:
- no logs are generated if I scan the container from the host.
- only the first one generates logs in my journalctl if I scan the host from the container
c_victim
.
docker networking iptables virtual-network
docker networking iptables virtual-network
asked Nov 13 '18 at 2:17
issrcissrc
12
12
add a comment |
add a comment |
0
active
oldest
votes
Your Answer
StackExchange.ifUsing("editor", function () {
StackExchange.using("externalEditor", function () {
StackExchange.using("snippets", function () {
StackExchange.snippets.init();
});
});
}, "code-snippets");
StackExchange.ready(function() {
var channelOptions = {
tags: "".split(" "),
id: "1"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);
StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled) {
StackExchange.using("snippets", function() {
createEditor();
});
}
else {
createEditor();
}
});
function createEditor() {
StackExchange.prepareEditor({
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: true,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: 10,
bindNavPrevention: true,
postfix: "",
imageUploader: {
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
},
onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
});
}
});
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f53272819%2fcatch-iptables-logs-from-container-to-host%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
0
active
oldest
votes
0
active
oldest
votes
active
oldest
votes
active
oldest
votes
Thanks for contributing an answer to Stack Overflow!
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
To learn more, see our tips on writing great answers.
Some of your past answers have not been well-received, and you're in danger of being blocked from answering.
Please pay close attention to the following guidance:
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
To learn more, see our tips on writing great answers.
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f53272819%2fcatch-iptables-logs-from-container-to-host%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown