+[[chapter_pve_firewall]]
ifdef::manvolnum[]
-PVE(8)
-======
-include::attributes.txt[]
-
+pve-firewall(8)
+===============
:pve-toplevel:
NAME
DESCRIPTION
-----------
endif::manvolnum[]
-
ifndef::manvolnum[]
{pve} Firewall
==============
-include::attributes.txt[]
+:pve-toplevel:
endif::manvolnum[]
-
ifdef::wiki[]
-:pve-toplevel:
:title: Firewall
endif::wiki[]
and aliases help to make that task easier.
While all configuration is stored on the cluster file system, the
-`iptables`-based firewall runs on each cluster node, and thus provides
+`iptables`-based firewall service runs on each cluster node, and thus provides
full isolation between virtual machines. The distributed nature of
this system also provides much higher bandwidth than a central
firewall solution.
or on a *Node* -> *Firewall*), or you can edit the configuration files
directly using your preferred editor.
-Firewall configuration files contains sections of key-value
+Firewall configuration files contain sections of key-value
pairs. Lines beginning with a `#` and blank lines are considered
-comments. Sections starts with a header line containing the section
+comments. Sections start with a header line containing the section
name enclosed in `[` and `]`.
+[[pve_firewall_cluster_wide_setup]]
Cluster Wide Setup
~~~~~~~~~~~~~~~~~~
-The cluster wide firewall configuration is stored at:
+The cluster-wide firewall configuration is stored at:
/etc/pve/firewall/cluster.fw
`[OPTIONS]`::
-This is used to set cluster wide firewall options.
+This is used to set cluster-wide firewall options.
include::pve-firewall-cluster-opts.adoc[]
`[RULES]`::
-This sections contains cluster wide firewall rules for all nodes.
+This sections contains cluster-wide firewall rules for all nodes.
`[IPSET <name>]`::
----
[OPTIONS]
-# enable firewall (cluster wide setting, default is disabled)
+# enable firewall (cluster-wide setting, default is disabled)
enable: 1
----
firewall rules to access the GUI from remote.
+[[pve_firewall_host_specific_configuration]]
Host Specific Configuration
~~~~~~~~~~~~~~~~~~~~~~~~~~~
This sections contains host specific firewall rules.
-
+[[pve_firewall_vm_container_configuration]]
VM/Container Configuration
~~~~~~~~~~~~~~~~~~~~~~~~~~
can selectively enable the firewall for each interface. This is
required in addition to the general firewall `enable` option.
-The firewall requires a special network device setup, so you need to
-restart the VM/container after enabling the firewall on a network
-interface.
-
Firewall Rules
--------------
IN SSH(ACCEPT) -i net0
IN SSH(ACCEPT) -i net0 # a comment
IN SSH(ACCEPT) -i net0 -source 192.168.2.192 # only allow SSH from 192.168.2.192
-IN SSH(ACCEPT) -i net0 -source 10.0.0.1-10.0.0.10 # accept SSH for ip range
-IN SSH(ACCEPT) -i net0 -source 10.0.0.1,10.0.0.2,10.0.0.3 #accept ssh for ip list
+IN SSH(ACCEPT) -i net0 -source 10.0.0.1-10.0.0.10 # accept SSH for IP range
+IN SSH(ACCEPT) -i net0 -source 10.0.0.1,10.0.0.2,10.0.0.3 #accept ssh for IP list
IN SSH(ACCEPT) -i net0 -source +mynetgroup # accept ssh for ipset mynetgroup
IN SSH(ACCEPT) -i net0 -source myserveralias #accept ssh for alias myserveralias
----
+[[pve_firewall_security_groups]]
Security Groups
---------------
GROUP webserver
----
-
+[[pve_firewall_ip_aliases]]
IP Aliases
----------
----
# /etc/pve/firewall/cluster.fw
[ALIASES]
-local_network 1.2.3.4 # use the single ip address
+local_network 1.2.3.4 # use the single IP address
----
-
+[[pve_firewall_ip_sets]]
IP Sets
-------
~~~~~~~~~~~~~~~~~~~~~~~~~~~~
This IP set applies only to host firewalls (not VM firewalls). Those
-IPs are allowed to do normal management tasks (PVE GUI, VNC, SPICE,
+IPs are allowed to do normal management tasks ({PVE} GUI, VNC, SPICE,
SSH).
The local cluster network is automatically added to this IP set (alias
----
-[[ipfilter-section]]
+[[pve_firewall_ipfilter_section]]
Standard IP set `ipfilter-net*`
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# iptables-save
+[[pve_firewall_default_rules]]
+Default firewall rules
+----------------------
+
+The following traffic is filtered by the default firewall configuration:
+
+Datacenter incoming/outgoing DROP/REJECT
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+If the input or output policy for the firewall is set to DROP or REJECT, the
+following traffic is still allowed for all {pve} hosts in the cluster:
+
+* traffic over the loopback interface
+* already established connections
+* traffic using the IGMP protocol
+* TCP traffic from management hosts to port 8006 in order to allow access to
+ the web interface
+* TCP traffic from management hosts to the port range 5900 to 5999 allowing
+ traffic for the VNC web console
+* TCP traffic from management hosts to port 3128 for connections to the SPICE
+ proxy
+* TCP traffic from management hosts to port 22 to allow ssh access
+* UDP traffic in the cluster network to ports 5405-5412 for corosync
+* UDP multicast traffic in the cluster network
+* ICMP traffic type 3 (Destination Unreachable), 4 (congestion control) or 11
+ (Time Exceeded)
+
+The following traffic is dropped, but not logged even with logging enabled:
+
+* TCP connections with invalid connection state
+* Broadcast, multicast and anycast traffic not related to corosync, i.e., not
+ coming through ports 5405-5412
+* TCP traffic to port 43
+* UDP traffic to ports 135 and 445
+* UDP traffic to the port range 137 to 139
+* UDP traffic form source port 137 to port range 1024 to 65535
+* UDP traffic to port 1900
+* TCP traffic to port 135, 139 and 445
+* UDP traffic originating from source port 53
+
+The rest of the traffic is dropped or rejected, respectively, and also logged.
+This may vary depending on the additional options enabled in
+*Firewall* -> *Options*, such as NDP, SMURFS and TCP flag filtering.
+
+[[pve_firewall_iptables_inspect]]
+Please inspect the output of the
+
+----
+ # iptables-save
+----
+
+system command to see the firewall chains and rules active on your system.
+This output is also included in a `System Report`, accessible over a node's
+subscription tab in the web GUI, or through the `pvereport` command-line tool.
+
+VM/CT incoming/outgoing DROP/REJECT
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+This drops or rejects all the traffic to the VMs, with some exceptions for
+DHCP, NDP, Router Advertisement, MAC and IP filtering depending on the set
+configuration. The same rules for dropping/rejecting packets are inherited
+from the datacenter, while the exceptions for accepted incoming/outgoing
+traffic of the host do not apply.
+
+Again, you can use xref:pve_firewall_iptables_inspect[iptables-save (see above)]
+to inspect all rules and chains applied.
+
+Logging of firewall rules
+-------------------------
+
+By default, all logging of traffic filtered by the firewall rules is disabled.
+To enable logging, the `loglevel` for incoming and/or outgoing traffic has to be
+set in *Firewall* -> *Options*. This can be done for the host as well as for the
+VM/CT firewall individually. By this, logging of {PVE}'s standard firewall rules
+is enabled and the output can be observed in *Firewall* -> *Log*.
+Further, only some dropped or rejected packets are logged for the standard rules
+(see xref:pve_firewall_default_rules[default firewall rules]).
+
+`loglevel` does not affect how much of the filtered traffic is logged. It
+changes a `LOGID` appended as prefix to the log output for easier filtering and
+post-processing.
+
+`loglevel` is one of the following flags:
+
+[[pve_firewall_log_levels]]
+[width="25%", options="header"]
+|===================
+| loglevel | LOGID
+| nolog | --
+| emerg | 0
+| alert | 1
+| crit | 2
+| err | 3
+| warning | 4
+| notice | 5
+| info | 6
+| debug | 7
+|===================
+
+A typical firewall log output looks like this:
+
+----
+VMID LOGID CHAIN TIMESTAMP POLICY: PACKET_DETAILS
+----
+
+In case of the host firewall, `VMID` is equal to 0.
+
+
+Logging of user defined firewall rules
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+In order to log packets filtered by user-defined firewall rules, it is possible
+to set a log-level parameter for each rule individually.
+This allows to log in a fine grained manner and independent of the log-level
+defined for the standard rules in *Firewall* -> *Options*.
+
+While the `loglevel` for each individual rule can be defined or changed easily
+in the web UI during creation or modification of the rule, it is possible to set
+this also via the corresponding `pvesh` API calls.
+
+Further, the log-level can also be set via the firewall configuration file by
+appending a `-log <loglevel>` to the selected rule (see
+xref:pve_firewall_log_levels[possible log-levels]).
+
+For example, the following two are identical:
+
+----
+IN REJECT -p icmp -log nolog
+IN REJECT -p icmp
+----
+
+whereas
+
+----
+IN REJECT -p icmp -log debug
+----
+
+produces a log output flagged with the `debug` level.
+
Tips and Tricks
---------------
Suricata IPS integration
~~~~~~~~~~~~~~~~~~~~~~~~
-If you want to use the http://suricata-ids.org/[Suricata IPS]
+If you want to use the https://suricata.io/[Suricata IPS]
(Intrusion Prevention System), it's possible.
Packets will be forwarded to the IPS only after the firewall ACCEPTed
level to allow neighbor discovery (NDP) packets to be sent and received.
Beside neighbor discovery NDP is also used for a couple of other things, like
-autoconfiguration and advertising routers.
+auto-configuration and advertising routers.
By default VMs are allowed to send out router solicitation messages (to query
for a router), and to receive router advertisement packets. This allows them to
(`ipfilter: 1`) option which can be enabled which has the same effect as adding
an `ipfilter-net*` ipset for each of the VM's network interfaces containing the
corresponding link local addresses. (See the
-<<ipfilter-section,Standard IP set `ipfilter-net*`>> section for details.)
+<<pve_firewall_ipfilter_section,Standard IP set `ipfilter-net*`>> section for details.)
Ports used by {pve}
-------------------
-* Web interface: 8006
-* VNC Web console: 5900-5999
-* SPICE proxy: 3128
-* sshd (used for cluster actions): 22
-* rpcbind: 111
-* corosync multicast (if you run a cluster): 5404, 5405 UDP
-
+* Web interface: 8006 (TCP, HTTP/1.1 over TLS)
+* VNC Web console: 5900-5999 (TCP, WebSocket)
+* SPICE proxy: 3128 (TCP)
+* sshd (used for cluster actions): 22 (TCP)
+* rpcbind: 111 (UDP)
+* sendmail: 25 (TCP, outgoing)
+* corosync cluster traffic: 5405-5412 UDP
+* live migration (VM memory and local-disk data): 60000-60050 (TCP)
ifdef::manvolnum[]