Configuring Felix

Configuration for Felix is read from one of four possible locations, in order, as follows.

  1. Environment variables.
  2. The Felix configuration file.
  3. Host specific configuration in etcd.
  4. Global configuration in etcd.

The value of any configuration parameter is the value read from the first location containing a value. If not set in any of these locations, most configuration parameters have defaults, and it should be rare to have to explicitly set them.

The full list of parameters which can be set is as follows.

Global configuration

Setting (Environment variable) Description Schema
DatastoreType (FELIX_DATASTORETYPE) The datastore that Felix should read endpoints and policy information from. [Default: etcdv2] etcdv2, Kubernetes
FelixHostname (FELIX_FELIXHOSTNAME) The hostname Felix reports to the plugin. Should be used if the hostname Felix autodetects is incorrect or does not match what the plugin will expect. [Default: socket.gethostname()] string
LogFilePath (FELIX_LOGFILEPATH) The full path to the Felix log. Set to none to disable file logging. [Default: /var/log/calico/felix.log] string
LogSeveritySys (FELIX_LOGSEVERITYSYS) The log severity above which logs are sent to the syslog. Set to NONE for no logging to syslog. [Default: INFO] DEBUG, INFO, WARNING, ERROR, CRITICAL, or NONE (case-insensitive)
LogSeverityFile (FELIX_LOGSEVERITYFILE) The log severity above which logs are sent to the log file. [Default: INFO] Same as LogSeveritySys
LogSeverityScreen (FELIX_LOGSEVERITYSCREEN) The log severity above which logs are sent to the stdout. [Default: INFO] Same as LogSeveritySys
PrometheusMetricsEnabled (FELIX_PROMETHEUSMETRICSENABLED) Set to true to enable the experimental Prometheus metrics server in Felix. [Default: false] boolean
PrometheusMetricsPort (FELIX_PROMETHEUSMETRICSPORT) Experimental: TCP port that the Prometheus metrics server should bind to. [Default: 9091] int
PrometheusGoMetricsEnabled (FELIX_PROMETHEUSGOMETRICSENABLED) Set to false to disable Go runtime metrics collection, which the Prometheus client does by default. This reduces the number of metrics reported, reducing Prometheus load. [Default: true] boolean
PrometheusProcessMetricsEnabled (FELIX_PROMETHEUSPROCESSMETRICSENABLED) Set to false to disable process metrics collection, which the Prometheus client does by default. This reduces the number of metrics reported, reducing Prometheus load. [Default: true] boolean
UsageReportingEnabled (FELIX_USAGEREPORTINGENABLED) Reports anonymous Calico version number and cluster size to projectcalico.org. Logs warnings returned by the usage server. For example, if a significant security vulnerability has been discovered in the version of Calico being used. [Default: true] boolean
FailsafeInboundHostPorts (FELIX_FAILSAFEINBOUNDHOSTPORTS) Comma-delimited list of UDP/TCP ports that Felix will allow incoming traffic to host endpoints on irrespective of the security policy. This is useful to avoid accidently cutting off a host with incorrect configuration. Each port should be specified as tcp:<port-number> or udp:<port-number>. For back-compatibility, if the protocol is not specified, it defaults to “tcp”. To disable all inbound host ports, use the value none. The default value allows ssh access and DHCP. [Default: tcp:22, udp:68] string
FailsafeOutboundHostPorts (FELIX_FAILSAFEOUTBOUNDHOSTPORTS) Comma-delimited list of UDP/TCP ports that Felix will allow outgoing traffic from host endpoints to irrespective of the security policy. This is useful to avoid accidently cutting off a host with incorrect configuration. Each port should be specified as tcp:<port-number> or udp:<port-number>. For back-compatibility, if the protocol is not specified, it defaults to “tcp”. To disable all outbound host ports, use the value none. The default value opens etcd’s standard ports to ensure that Felix does not get cut off from etcd as well as allowing DHCP and DNS. [Default: tcp:2379, tcp:2380, tcp:4001, tcp:7001, udp:53, udp:67] string
ReportingIntervalSecs (FELIX_REPORTINGINTERVALSECS) Interval at which Felix reports its status into the datastore or 0 to disable. Must be non-zero in OpenStack deployments. [Default: 30] int
ReportingTTLSecs (FELIX_REPORTINGTTLSECS) Time-to-live setting for process-wide status reports. [Default: 90] int
IpInIpMtu (FELIX_IPINIPMTU) The MTU to set on the tunnel device. See Configuring MTU [Default: 1440] int

etcdv2 datastore configuration

Setting (Environment variable) Description Schema
EtcdEndpoints (FELIX_ETCDENDPOINTS) Comma-delimited list of etcd endpoints to connect to; for example http://etcd1:2379,http://etcd2:2379. EtcdScheme://EtcdAddr
Deprecated EtcdAddr (FELIX_ETCDADDR) The location (IP / hostname and port) of the etcd node or proxy that Felix should connect to. [Default: 127.0.0.1:2379] string
Deprecated EtcdScheme (FELIX_ETCDSCHEME) The protocol type (http or https) of the etcd node or proxy that Felix connects to. [Default: http] http, https
EtcdKeyFile (FELIX_ETCDKEYFILE) The full path to the etcd private key file. string
EtcdCertFile (FELIX_ETCDCERTFILE) The full path to the etcd certificate file. string
EtcdCaFile (FELIX_ETCDCAFILE) The full path to the etcd Certificate Authority certificate file. To disable authentication of the server by Felix, set the value to none. [Default: /etc/ssl/certs/ca-certificates.crt] string

Kubernetes datastore configuration

Setting (Environment variable) Description Schema
N/A The Kubernetes datastore driver reads its configuration from Kubernetes-provided environment variables.  

iptables dataplane configuration

Setting (Environment variable) Description Schema
DefaultEndpointToHostAction (FELIX_DEFAULTENDPOINTTOHOSTACTION) This parameter controls what happens to traffic that goes from a workload endpoint to the host itself (after the traffic hits the endpoint egress policy). By default Calico blocks traffic from workload endpoints to the host itself with an iptables “DROP” action. If you want to allow some or all traffic from endpoint to host, set this parameter to RETURN or ACCEPT. Use RETURN if you have your own rules in the iptables “INPUT” chain; Calico will insert its rules at the top of that chain, then “RETURN” packets to the “INPUT” chain once it has completed processing workload endpoint egress policy. Use ACCEPT to unconditionally accept packets from workloads after processing workload endpoint egress policy. [Default: DROP] DROP, RETURN, ACCEPT (case insensitive)
ignoreLooseRPF (FELIX_IGNORELOOSERPF) Set to true to allow Felix to run on systems with loose reverse path forwarding (RPF). Warning: Calico relies on “strict” RPF checking being enabled to prevent workloads, such as VMs and privileged containers, from spoofing their IP addresses and impersonating other workloads (or hosts). Only enable this flag if you need to run with “loose” RPF and you either trust your workloads or have another mechanism in place to prevent spoofing. true,false
IptablesFilterAllowAction (FELIX_IPTABLESFILTERALLOWACTION) This parameter controls what happens to traffic that is allowed by a Felix policy chain in the iptables filter table (i.e. a normal policy chain). The default will immediately ACCEPT the traffic. Use RETURN to send the traffic back up to the system chains for further processing. [Default: ACCEPT] ACCEPT, RETURN (case insensitive)
IptablesMangleAllowAction (FELIX_IPTABLESMANGLEALLOWACTION) This parameter controls what happens to traffic that is allowed by a Felix policy chain in the iptables mangle table (i.e. a pre-DNAT policy chain). The default will immediately ACCEPT the traffic. Use RETURN to send the traffic back up to the system chains for further processing. [Default: ACCEPT] ACCEPT, RETURN (case insensitive)
IptablesMarkMask (FELIX_IPTABLESMARKMASK) Mask that Felix selects its IPTables Mark bits from. Should be a 32 bit hexadecimal number with at least 8 bits set, none of which clash with any other mark bits in use on the system. [Default: 0xff000000] netmask
IptablesRefreshInterval (FELIX_IPTABLESREFRESHINTERVAL) Period, in seconds, at which Felix re-checks all iptables state to ensure that no other process has accidentally broken Calico’s rules. Set to 0 to disable iptables refresh. [Default: 90] int
IptablesPostWriteCheckIntervalSecs (FELIX_IPTABLESPOSTWRITECHECKINTERVALSECS) Period, in seconds, after Felix has done a write to the dataplane that it schedules an extra read back in order to check the write was not clobbered by another process. This should only occur if another application on the system doesn’t respect the iptables lock. [Default: 1] int
RouteRefreshInterval (FELIX_ROUTEREFRESHINTERVAL) Period, in seconds, at which Felix re-checks the routes in the dataplane to ensure that no other process has accidentally broken Calico’s rules. Set to 0 to disable route refresh. [Default: 90] int
IpsetsRefreshInterval (FELIX_IPSETSREFRESHINTERVAL) Period, in seconds, at which Felix re-checks the IP sets in the dataplane to ensure that no other process has accidentally broken Calico’s rules. Set to 0 to disable IP sets refresh. Note: the default for this value is lower than the other refresh intervals as a workaround for a Linux kernel bug that was fixed in kernel version 4.11. If you are using v4.11 or greater you may want to set this to, a higher value to reduce Felix CPU usage. [Default: 10] int
MaxIpsetSize (FELIX_MAXIPSETSIZE) Maximum size for the ipsets used by Felix to implement tags. Should be set to a number that is greater than the maximum number of IP addresses that are ever expected in a tag. [Default: 1048576] int
ChainInsertMode (FELIX_CHAININSERTMODE) Controls whether Felix hooks the kernel’s top-level iptables chains by inserting a rule at the top of the chain or by appending a rule at the bottom. insert is the safe default since it prevents Calico’s rules from being bypassed. If you switch to append mode, be sure that the other rules in the chains signal acceptance by falling through to the Calico rules, otherwise the Calico policy will be bypassed. [Default: insert] INSERT, APPEND (case insensitive)
LogPrefix (FELIX_LOGPREFIX) The log prefix that Felix uses when rendering LOG rules. [Default: calico-packet] string
IptablesLockTimeoutSecs (FELIX_IPTABLESLOCKTIMEOUTSECS) Time, in seconds, that Felix will wait for the iptables lock, or 0, to disable. To use this feature, Felix must share the iptables lock file with all other processes that also take the lock. When running Felix inside a container, this requires the /run directory of the host to be mounted into the calico/node or calico/felix container. [Default: 0 disabled] int
IptablesLockFilePath (FELIX_IPTABLESLOCKFILEPATH) Location of the iptables lock file. You may need to change this if the lock file is not in its standard location (for example if you have mapped it into Felix’s container at a different path). [Default: /run/xtables.lock] string
IptablesLockProbeIntervalMillis (FELIX_IPTABLESLOCKPROBEINTERVALMILLIS) Time, in milliseconds, that Felix will wait between attempts to acquire the iptables lock if it is not available. Lower values make Felix more responsive when the lock is contended, but use more CPU. [Default: 50] int
NetlinkTimeoutSecs (FELIX_NETLINKTIMEOUTSECS) Time, in seconds, that Felix will wait for netlink (i.e. routing table list/update) operations to complete before giving up and retrying. [Default: 10] float

OpenStack specific configuration

Setting (Environment variable) Description Schema
MetadataAddr (FELIX_METADATAADDR) The IP address or domain name of the server that can answer VM queries for cloud-init metadata. In OpenStack, this corresponds to the machine running nova-api (or in Ubuntu, nova-api-metadata). A value of none (case insensitive) means that Felix should not set up any NAT rule for the metadata path. [Default: 127.0.0.1] IPv4, hostname, none
MetadataPort (FELIX_METADATAPORT) The port of the metadata server. This, combined with global.MetadataAddr (if not ‘None’), is used to set up a NAT rule, from 169.254.169.254:80 to MetadataAddr:MetadataPort. In most cases this should not need to be changed [Default: 8775]. int

Bare metal specific configuration

Setting (Environment variable) Description Schema
InterfacePrefix (FELIX_INTERFACEPREFIX) The interface name prefix that identifies workload endpoints and so distinguishes them from host endpoint interfaces. Note: in environments other than bare metal, the orchestrators configure this appropriately. For example our Kubernetes and Docker integrations set the ‘cali’ value, and our OpenStack integration sets the ‘tap’ value. [Default: cali] string

Environment variables

The highest priority of configuration is that read from environment variables. To set a configuration parameter via an environment variable, set the environment variable formed by taking FELIX_ and appending the uppercase form of the variable name. For example, to set the etcd address, set the environment variable FELIX_ETCDADDR. Other examples include FELIX_ETCDSCHEME, FELIX_ETCDKEYFILE, FELIX_ETCDCERTFILE, FELIX_ETCDCAFILE, FELIX_FELIXHOSTNAME, FELIX_LOGFILEPATH and FELIX_METADATAADDR.

Configuration file

On startup, Felix reads an ini-style configuration file. The path to this file defaults to /etc/calico/felix.cfg but can be overridden using the -c or --config-file options on the command line. If the file exists, then it is read (ignoring section names) and all parameters are set from it.

In OpenStack, we recommend putting all configuration into configuration files, since the etcd database is transient (and may be recreated by the OpenStack plugin in certain error cases). However, in a Docker environment the use of environment variables or etcd is often more convenient.

Datastore

Felix also reads configuration parameters from the datastore. It supports a global setting and a per-host override. Datastore-based configuration can be set using the --raw=felix option of the calicoctl tool. For example, to set a per-host override for “myhost” to move the log file to /tmp/felix.log:

./calicoctl config set --raw=felix --node=myhost LogFilePath /tmp/felix.log

(For a global setting, omit the --node= option.)

For more information, see the calicoctl config documentation.