Google Security Operations forwarder for Linux
This document describes how to install and configure the forwarder on Linux. To install the forwarder on Windows, see Windows forwarder.
Forwarder is used to send logs from the customer environment to the Google Security Operations instance. This is used when the customers want to send the logs directly to Google Security Operations, and don't want to use the cloud buckets to ingest data, or the logtype does not support direct ingestion using 3rd party API. The forwarder can be used as a ready to deploy solution, instead of manually incorporating the ingestion API.
You can install the forwarder on a variety of Linux distributions including Debian, Ubuntu, Red Hat, and Suse. Google Cloud provides the software using a Docker container. You can run and manage the Docker container on either a physical or virtual machine running Linux.
System requirements
The following are general recommendations. For recommendations specific to your system, contact Google Security Operations Support.
RAM—1 GB for each collected data type (collector) that Google Security Operations accepts for ingestion. For example, if you have specified 4 different collectors, you need 4 GB of RAM to collect data for all four collectors.
CPU—2 CPUs are sufficient to handle less than 10,000 events per second (EPS) (total for all data types). If you expect to forward more than 10,000 EPS, provision 4 to 6 CPUs.
Disk—100 MB of disk space is sufficient, regardless of how much data the Google Security Operations forwarder handles. If you need to buffer backlogged messages to disk as opposed to memory, see Disk Buffering. The Google Security Operations forwarder buffers to memory by default.
Limitations
Data feeds have a maximum log line size of 4 MB.
Google IP address ranges
You might need the IP address range to open when setting up a Forwarder configuration, such as when setting up the configuration for your firewall. It's not possible for Google to provide a specific list of IP addresses. However, you can obtain Google IP address ranges.
Verify the firewall configuration
Any firewalls or authenticated proxies in between the Google Security Operations forwarder container and the Internet require rules to open access to the following hosts:
Connection Type | Destination | Port |
TCP | malachiteingestion-pa.googleapis.com | 443 |
TCP | asia-northeast1-malachiteingestion-pa.googleapis.com | 443 |
TCP | asia-south1-malachiteingestion-pa.googleapis.com | 443 |
TCP | asia-southeast1-malachiteingestion-pa.googleapis.com | 443 |
TCP | australia-southeast1-malachiteingestion-pa.googleapis.com | 443 |
TCP | europe-malachiteingestion-pa.googleapis.com | 443 |
TCP | europe-west2-malachiteingestion-pa.googleapis.com | 443 |
TCP | europe-west3-malachiteingestion-pa.googleapis.com | 443 |
TCP | europe-west6-malachiteingestion-pa.googleapis.com | 443 |
TCP | europe-west12-malachiteingestion-pa.googleapis.com | 443 |
TCP | me-central1-malachiteingestion-pa.googleapis.com | 443 |
TCP | me-central2-malachiteingestion-pa.googleapis.com | 443 |
TCP | me-west1-malachiteingestion-pa.googleapis.com | 443 |
TCP | northamerica-northeast2-malachiteingestion-pa.googleapis.com | 443 |
TCP | accounts.google.com | 443 |
TCP | gcr.io | 443 |
TCP | cloud.google.com/artifact-registry | 443 |
TCP | oauth2.googleapis.com | 443 |
TCP | storage.googleapis.com | 443 |
Customize the configuration files
Google Cloud tailors the configuration files to the forwarder instance with specific metadata as shown in the output section. You can download the configuration file as per your requirements and include information about the log types to be ingested under the collectors section. For more information on the configuration settings, see Configuration settings reference.
Configure the Linux forwarder
To configure the Linux forwarder through the UI, see Manage forwarder configurations through the Google SecOps UI.
To configure the Linux forwarder manually, do the following:
Make a copy of the configuration file template provided with the software.
Download the configuration file through the UI.
Save the two files in the same directory using the following naming convention:
FORWARDER_NAME
.conf—Use this file to define the configuration settings related to log ingestion.FORWARDER_NAME
_auth.conf—Use this file to define the authorization credentials.Modify the files to include the configuration for your forwarder instance. Use the samples provided in this document as a reference.
Ensure that an entry exists for each input in the
FORWARDER_NAME
_auth.conf file even if the input doesn't have corresponding authentication details. This is required to map the data correctly.
Any changes made to the configuration file will be automatically applied by the forwarder within 5 minutes.
Sample configuration
The following code sample shows the format of the configuration files for a forwarder. For details about the settings for each type of ingestion mechanism, such as Splunk or Syslog, see Collect Data.
The FORWARDER_NAME.conf file
output: url: malachiteingestion-pa.googleapis.com:443 identity: identity: collector_id: COLLECTOR_ID \ customer_id: CUSTOMER_ID \ collectors: - syslog: common: enabled: true data_type: "WINDOWS_DHCP" data_hint: batch_n_seconds: 10 batch_n_bytes: 1048576 tcp_address: 0.0.0.0:10514 udp_address: 0.0.0.0:10514 connection_timeout_sec: 60 tcp_buffer_size: 524288 - syslog: common: enabled: true data_type: "WINDOWS_DNS" data_hint: batch_n_seconds: 10 batch_n_bytes: 1048576 tcp_address: 0.0.0.0:10515 connection_timeout_sec: 60 tcp_buffer_size: 524288
The FORWARDER_NAME_auth.conf file
output: identity: secret_key: | { "type": "service_account", "project_id": "PROJECT_ID" \, "private_key_id": "PRIVATE_KEY_ID" \, "private_key": "-----BEGIN PRIVATE KEY-----\\"PRIVATE_KEY" \n-----END PRIVATE KEY-----\n", "client_email": "CLIENT_EMAIL" \, "client_id": "CLIENT_ID" \, "auth_uri": "https://accounts.google.com/o/oauth2/auth", "token_uri": "https://oauth2.googleapis.com/token", "auth_provider_x509_cert_url": "https://www.googleapis.com/oauth2/v1/certs", "client_x509_cert_url": "https://www.googleapis.com/robot/v1/metadata/x509/example-account-1%40example-account.iam.gserviceaccount.com" } collectors: - syslog: - syslog: certificate: "../forwarder/inputs/testdata/localhost.pem" certificate_key: "../forwarder/inputs/testdata/localhost.key"
This two file system lets you store authentication credentials in a separate
file for enhanced security. You can store the FORWARDER_NAME
.conf
file in a
version control repository or any open configuration management system. You can store the
FORWARDER_NAME
_auth.conf file directly in the physical or virtual machine running the forwarder.
Sample Configuration (Single file)
output: url: malachiteingestion-pa.googleapis.com:443 identity: identity: collector_id: "COLLECTOR_ID" \ customer_id: "CUSTOMER_ID" \ secret_key: | { "type": "service_account", "project_id": "PROJECT_ID" \, "private_key_id": "PRIVATE_KEY_ID" \, "private_key": "-----BEGIN PRIVATE KEY-----\ "PRIVATE_KEY" \n-----END PRIVATE KEY-----\n", "client_email": "CLIENT_EMAIL" \, "client_id": "CLIENT_ID" \, "auth_uri": "https://accounts.google.com/o/oauth2/auth", "token_uri": "https://oauth2.googleapis.com/token", "auth_provider_x509_cert_url": "https://www.googleapis.com/oauth2/v1/certs", "client_x509_cert_url": "https://www.googleapis.com/robot/v1/metadata/x509/malachite-test-1%40malachite-test.iam.gserviceaccount.com" } collectors: - syslog: common: enabled: true data_type: "WINDOWS_DHCP" data_hint: batch_n_seconds: 10 batch_n_bytes: 1048576 tcp_address: 0.0.0.0:10514 udp_address: 0.0.0.0:10514 connection_timeout_sec: 60 tcp_buffer_size: 524288 - syslog: common: enabled: true data_type: "WINDOWS_DNS" data_hint: batch_n_seconds: 10 batch_n_bytes: 1048576 tcp_address: 0.0.0.0:10515 connection_timeout_sec: 60 certificate: "../forwarder/inputs/testdata/localhost.pem" certificate_key: "../forwarder/inputs/testdata/localhost.key" tcp_buffer_size: 524288
If you are using the single configuration file and want to move to the two file system, do the following:
- Create a copy of your existing configuration.
- Save one file as the
FORWARDER_NAME
.conf file and delete the authorization credentials from the file. - Save the other file as
FORWARDER_NAME
_auth.conf file and delete all the non-authorization data from the file. Use the sample configuration files given in this guide as reference. - Make sure that you follow the naming convention and other guidelines mentioned in the section Customize the configuration files.
Install Docker
The installation of Docker is dependent on the host environment. You can install Docker on different host operating systems. Google Cloud provides limited documentation to assist you in installing Docker on several of the more popular Linux distributions. However, Docker is open source and all necessary documentation is already available. For instructions on docker installation, refer to Docker Documentation.
Once Docker is installed on your system, the Google Security Operations forwarder installation process is similar to any type of Linux distribution.
To check if Docker is installed properly on your system, execute the following command (elevated privileges):
docker ps
The following response indicates that Docker has been installed properly:
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
Useful Docker commands
You can gather additional information about the Docker installation using the following command:
docker info
The Docker service could be disabled by default. To check if it is disabled, execute the following command:
systemctl is-enabled docker
To enable the Docker service and start it immediately, execute one of the following commands:
sudo systemctl enable --now docker
sudo systemctl enable /usr/lib/systemd/system/docker.service
Output:
Created symlink /etc/systemd/system/multi-user.target.wants/docker.service → /lib/systemd/system/docker.service
When you start a forwarder, execute the following command to set the forwarder to auto-restart:
sudo docker run --restart=always `IMAGE_NAME`
IMAGE_NAME
is the forwarder image name.To check the status and details of the Docker service, execute the following command:
sudo systemctl status docker
Output:
● docker.service - Docker Application Container Engine Loaded: loaded (/lib/systemd/system/docker.service; enabled; vendor preset: enabled) Active: active (running) since Sat 2020-07-18 11:14:05 UTC; 15s ago TriggeredBy: ● docker.socket Docs: https://docs.docker.com Main PID: 263 (dockerd) Tasks: 20 Memory: 100.4M CGroup: /system.slice/docker.service └─263 /usr/bin/dockerd -H fd:// --containerd=/run/containerd/containerd.sock Jul 18 11:14:05 swarm-kraken dockerd[263]: time="2020-07-18T11:14:05.713787002Z" level=info msg="API listen on /run/docker.sock" Jul 18 11:14:05 swarm-kraken systemd[1]: Started Docker Application Container Engine
If you have any issues with Docker, the Google Security Operations support team can request the output from this command to help and debug with the issue.
Install the forwarder on Linux
This section describes how to install the Google Security Operations Forwarder using a Docker container on a Linux system.
Step 1. Download, transfer, and install the forwarder configuration files
Google Security Operations provides forwarder configuration files specific to your operating system (Linux or Windows). You can download the configuration file as per your requirements. After you complete the following steps, transfer the configuration files from your laptop to your forwarder /opt/chronicle/config
directory within the user's home directory.
Connect to the host of the Linux forwarder using terminal.
Create a new user on the host of the Linux forwarder.
adduser
USERNAME
passwdUSERNAME
usermod -aG wheelUSERNAME
Change directory to the home directory of the new user that runs the Docker Container.
Create a directory to store the Google Security Operations forwarder configuration files:
mkdir -p /opt/chronicle/config
Change directory.
cd /opt/chronicle/config
Once files have been transferred, ensure that the configuration files are located in the /opt/chronicle/config directory:
ls -l
Step 2. Run the forwarder within the Docker container
You can use the following procedures to start the Google Security Operations forwarder for the first time as well as to upgrade to the latest version of the Google Security Operations container:
The --log-opt
options have been available since Docker
1.13. These options limit the size of the container log files and
must be used as long as your version of Docker supports them.
If you are upgrading, start by cleaning up any previous Docker runs. In the following example, the name of the Docker container is
cfps
. Obtain the latest Docker image from Google Cloud with thedocker pull
command as shown.docker stop cfps
docker rm cfps
Obtain the latest Docker image from Google Cloud:
docker pull gcr.io/chronicle-container/cf_production_stable
Start Google Security Operations forwarder from the Docker container:
docker run \ --detach \ --name cfps \ --restart=always \ --log-opt max-size=100m \ --log-opt max-file=10 \ --net=host \ -v /opt/chronicle/config:/opt/chronicle/external \ gcr.io/chronicle-container/cf_production_stable
View forwarder logs
To view the Google Security Operations forwarder logs, execute the following command:
sudo docker logs cfps
To view the path of the file in which the logs are stored, execute the following command:
docker inspect --format='{{.LogPath}}' CONTAINER_NAME
To view the live running logs, execute the following command:
sudo docker logs cfps -f
To store the logs in a file, execute the following command:
sudo docker logs cfps &> logs.txt
Uninstall the forwarder
The following Docker commands help you to stop and uninstall or remove the Google Security Operations forwarder.
To stop or uninstall the forwarder container:
docker stop cfps
To remove the forwarder container:
docker rm cfps
Update the forwarder
The Google Security Operations forwarder has two parts and is upgraded as follows:
Forwarder Bundle—Is automatically updated and a restart is not required.
Forwarder Docker image—Is updated manually after stopping the existing forwarder and starting a new instance as stated in Step 2.
Collect data
The following sections help you configure the Google Security Operations forwarder to ingest different types of data, which is forwarded to the Google Security Operations instance.
Collect Splunk data
You can configure the Google Security Operations forwarder to forward your Splunk data to Google Security Operations. Google Cloud configures Google Security Operations forwarder with the following information to forward your data from Splunk:
URL for the Splunk REST API (for example, https://10.0.113.15:8089).
Splunk queries to generate data for each of the required data types (for example, index=dns).
FORWARDER_NAME.conf output: collectors: - splunk: common: enabled: true data_type: WINDOWS_DNS data_hint: "#fields ts uid id.orig_h id.orig_p id.resp_h id.resp_p proto trans_id query qclass qclass_name" batch_n_seconds: 10 batch_n_bytes: 819200 url: https://127.0.0.1:8089 is_ignore_cert: true minimum_window_size: 10s maximum_window_size: 30s query_string: search index=* sourcetype=dns query_mode: realtime
- Make your Splunk account credentials available to the Google Security Operations
forwarder. You can do this by creating a
creds.txt
file.
To use a creds.txt
file:
Create a local file for your Splunk credentials and name it
creds.txt
.Place your username on the first line and the password on the second line:
cat creds.txt myusername mypassword
To use the Google Security Operations forwarder to access a Splunk instance, copy the
creds.txt
file to the config directory (the same directory where the configuration files reside). For example:cp creds.txt /opt/chronicle/config/creds.txt
Verify the
creds.txt
file is in its proper location:ls /opt/chronicle/config
Collect syslog data
Google Security Operations forwarder can work as a Syslog server. You can configure any appliance or server that supports sending syslog data over a TCP or UDP connection to forward their data to Google Security Operations forwarder. You can control the exact data that the appliance or the server sends to the Google Security Operations forwarder. The Google Security Operations forwarder can then forward the data to Google Security Operations.
The FORWARDER_NAME
.conf configuration file (provided by
Google Cloud) specifies which ports to monitor for each type of
forwarded data (for example, port 10514). By default, the Google Security Operations
forwarder accepts both TCP and UDP connections.
Configure rsyslog
To configure rsyslog, you need to specify a target for each port (for example, each data type). Consult your system documentation for the correct syntax. The following examples illustrate the rsyslog target configuration:
TCP log traffic:
dns.* @@192.168.0.12:10514
UDP log traffic:
dns.* @192.168.0.12:10514
Enable TLS for syslog configurations
You can enable TLS for the Syslog connection to the Google Security Operations
forwarder. In the Google Security Operations forwarder configuration file
(FORWARDER_NAME
.conf), specify the location of your own
generated certificate and certificate key as shown in the following example:
certificate | "/opt/chronicle/external/certs/client_generated_cert.pem" |
certificate_key | "/opt/chronicle/external/certs/client_generated_cert.key" |
Based on the example shown, modify the Google Security Operations forwarder
configuration file (FORWARDER_NAME
.conf) as follows:
collectors: - syslog: common: enabled: true data_type: WINDOWS_DNS data_hint: batch_n_seconds: 10 batch_n_bytes: 1048576 tcp_address: 0.0.0.0:10515 tcp_buffer_size: 65536 connection_timeout_sec: 60 certificate: "/opt/chronicle/external/certs/client_generated_cert.pem" certificate_key: "/opt/chronicle/external/certs/client_generated_cert.key" minimum_tls_version: "TLSv1_3"
Few important points to note:
You can configure the TCP buffer size. The default TCP buffer size is 64 KB.
The default and recommended value for connection_timeout is 60 seconds. The TCP connection gets terminated if the connection is inactive for a specified time.
The minimum TLS version is checked against the TLS version of the input request. The TLS version of the input request should be greater than the minimum TLS version. The minimum TLS version should be one of the following values: TLSv1_0, TLSv1_1, TLSv1_2, TLSv1_3.
You can create a certs directory under the configuration directory and store the certificate files there.
Collect file data
A file collector is designed to fetch the logs from a file. The file should be bound to the Docker container.
Use this if you want to manually upload logs from a single log file. This can be used to backfill logs for a particular log file.
Start the Google Security Operations forwarder from the Docker container:
docker run \ --detach \ --name cfps \ --log-opt max-size=100m \ --log-opt max-file=10 \ --net=host \ -v /opt/chronicle/config:/opt/chronicle/external \ -v /var/log/crowdstrike/falconhostclient:/opt/chronicle/edr \ gcr.io/chronicle-container/cf_production_stable
This docker run command is critical to map the load volume to the container.
Based on this example, you should modify the Google Security Operations forwarder
configuration (FORWARDER_NAME.conf
file) as follows.
The sample.txt
file should be present in the
/var/log/crowdstrike/falconhostclient
folder.
collectors: - file: common: enabled: true data_type: CS_EDR data_hint: batch_n_seconds: 10 batch_n_bytes: 1048576 file_path: /opt/chronicle/edr/sample.txt filter:
Flag configurations
skip_seek_to_end
(bool): This flag is set to false
by default and the file
input only sends new log lines as input. Setting this to true
causes all the
previous log lines to be sent again during forwarder restarts. This causes log
duplication. Setting this flag to true
is helpful in certain
situations (for example, during outages), because restarting the forwarder sends the
missing log lines again.
poll
(bool): File collector uses the Tail library to check for any changes in
the file system. By setting this flag to true
, the Tail library uses the polling
method instead of the default notify method.
Collect packet data
Google Security Operations forwarder can capture packets directly from a network interface using libcap on Linux. For more information on libcap, refer to libcap - Linux manual page.
Packets are captured and sent to Google Security Operations instead of log entries. Packet capture is handled from a local interface only. To enable packet capture for your system, contact Google Security Operations support.
Google Cloud configures Google Security Operations forwarder with the Berkeley Packet Filter (BPF) expression used when capturing packets (for example, port 53 and not localhost). For more information, refer to Berkeley packet filters.
Collect data from Kafka topic
You can ingest data from the Kafka topics just like you can from syslog. The consumer groups are leveraged to enable you to deploy up to 3 Forwarders and pull data from the same Kafka topic. For more information, refer to Kafka.
For more information on Kafka consumer groups, see the following: https://docs.confluent.io/platform/current/clients/consumer.html
Example configuration: Kafka input
The following forwarder configuration shows how to setup the forwarder to ingest data from the Kafka topics.
The FORWARDER_NAME.conf file
collectors: - kafka: common: batch_n_bytes: 1048576 batch_n_seconds: 10 data_hint: null data_type:NIX_SYSTEM
enabled: true topic: example-topic group_id: chronicle-forwarder timeout: 60s brokers: ["broker-1:9092", "broker-2:9093"] tls: insecureSkipVerify: true certificate: "/path/to/cert.pem" certificate_key: "/path/to/cert.key" - syslog: common: batch_n_bytes: 1048576 batch_n_seconds: 10 data_hint: null data_type:WINEVTLOG
enabled: true tcp_address: 0.0.0.0:30001 connection_timeout_sec: 60
The FORWARDER_NAME_auth.conf file
collectors: - kafka: username: user password: password - syslog:
Collect WebProxy data
The Google Security Operations forwarder can capture WebProxy data directly from a network interface using libcap on Linux. For more information on libcap, see libcap - Linux manual page. To enable WebProxy data capture for your system, contact Google Security Operations Support.
Modify the Google Security Operations forwarder configuration (FORWARDER_NAME.conf
file)
as follows:
- webproxy:
common:
enabled : true
data_type: <Your LogType>
batch_n_seconds: 10
batch_n_bytes: 1048576
interface: any
bpf: tcp and dst port 80
Customize configurations
The following table lists important parameters used in the forwarder configuration file.
Parameter | Description |
---|---|
data_type | The type of log data that the collector can collect and process. |
metadata | Metadata, which overrides global metadata. |
max_file_buffer_bytes | Maximum number of bytes that can be accumulated in the disk or file buffer. The default value is 1073741824 , which is 1 GB. |
max_memory_buffer_bytes | Maximum number of bytes that can be accumulated in the memory buffer. The
default value is 1073741824 , which is 1 GB. |
write_to_disk_dir_path | The path to be used for file or disk buffer. |
write_to_disk_buffer_enabled | If true , disk buffer is used instead of memory buffer. The default value is false .
|
batch_n_bytes | Maximum number of bytes that can be accumulated by the collector after
which the data is batched. The default value is 1048576 , which is
1 MB. |
batch_n_seconds | The number of seconds after which the data gathered by the collector is batched. The default value is 11 seconds. |
data_hint | Data format that the collector can receive (usually the log file header that describes the format). |
For an extensive list of parameters used in the configuration file, see Forwarder configuration fields and Collector configuration fields.
Toggle data compression
Log compression reduces network bandwidth consumption when transferring logs to Google Security Operations. However, the compression might cause an increase in CPU usage. The tradeoff between CPU usage and bandwidth depends on many factors, including the type of log data, the compressibility of that data, the availability of CPU cycles on the host running the forwarder and the need for reducing network bandwidth consumption.
For example, text based logs compress well and can provide substantial bandwidth savings with low CPU usage. However, encrypted payloads of raw packets don't compress well and incur higher CPU usage.
By default, log compression is disabled. Enabling log compression might reduce bandwidth consumption. However, enabling log compression might also increase CPU usage. Be aware of the trade off.
To enable log compression, set the compression field to true in the Google Security Operations forwarder configuration file as shown in the following example:
The FORWARDER_NAME.conf file
output: compression: true url: malachiteingestion-pa.googleapis.com:443 identity: identity: collector_id: 10479925-878c-11e7-9421-10604b7cb5c1 customer_id: ebdc4bb9-878b-11e7-8455-10604b7cb5c1 ...
The FORWARDER_NAME_auth.conf file
output: identity: secret_key: | { "type": "service_account", ... }
Configure disk buffering
Disk buffering lets you to buffer backlogged messages to disk as opposed to memory. The backlogged messages can be stored in case the forwarder crashes or the underlying host crashes. Be aware that enabling disk buffering can affect performance.
If disk buffering is disabled, the forwarder uses 1 GB of memory (RAM) for each log type (for example, per connector). Specify the max_memory_buffer_bytes configuration parameter. The maximum memory allowed is 4 GB.
You can configure automatic memory buffering to use a dynamically shared buffer across collectors, which deals better with spikes in traffic. To enable the dynamically shared buffer, add the following in your forwarder config:
auto_buffer: enabled: true target_memory_utilization: 80
If automatic disk buffering is enabled but
target_memory_utilization
is not defined, it uses a default value
of 70
.
If you are running the forwarder using Docker, Google recommends mounting a volume separate from your configuration volume for isolation purposes. Also, each input should be isolated with its own directory or volume to avoid conflicts.
Example configuration: disk buffering
The following configuration includes syntax to enable disk buffering:
collectors: - syslog: common: write_to_disk_buffer_enabled: true # /buffers/NIX_SYSTEM
is part of the external mounted volume for the forwarder write_to_disk_dir_path: /buffers/NIX_SYSTEM
max_file_buffer_bytes: 1073741824 batch_n_bytes: 1048576 batch_n_seconds: 10 data_hint: null data_type:NIX_SYSTEM
enabled: true tcp_address: 0.0.0.0:30000 connection_timeout_sec: 60 - syslog: common: batch_n_bytes: 1048576 batch_n_seconds: 10 data_hint: null data_type:WINEVTLOG
enabled: true tcp_address: 0.0.0.0:30001 connection_timeout_sec: 60
Set regular expression filters
Regular expression filters enable you to filter logs based on regular expression matches against raw logs.
The filters employ the RE2 syntax described here: https://github.com/google/re2/wiki/Syntax
The filters must include a regular expression and, optionally, define a behavior when there is a match. The default behavior on a match is block (you can also explicitly configure it as block).
Alternatively, you can specify filters with the allow
behavior. If you specify
any allow
filters, the forwarder blocks any logs that don't match at least one
allow
filter.
It is possible to define an arbitrary number of filters. Block filters take
precedence over allow
filters.
When filters are defined, they must be assigned a name. The names of active filters will be reported to Google Security Operations using Forwarder health metrics. Filters defined at the root of the configuration are merged with filters defined at the collector level. The collector level filters take precedence in cases of conflicting names. If no filters are defined either at the root or collector level, the behavior is to allow all.
Example configuration: regular expression filters
In the following Forwarder configuration, the WINEVTLOG
logs that
don't match the root filter (allow_filter
) are blocked. Given the regular
expression, the filter only allows logs with priorities between 0 and 99.
However, any NIX_SYSTEM
logs containing 'foo' or 'bar' are blocked,
despite the allow_filter
. This is because the filters use a logical OR. All
logs are processed until a filter is triggered.
regex_filters: allow_filter: regexp: ^<[1-9][0-9]?$>.*$ behavior_on_match: allow collectors: - syslog: common: regex_filters: block_filter_1: regexp: ^.*foo.*$ behavior_on_match: block block_filter_2: regexp: ^.*bar.*$ batch_n_bytes: 1048576 batch_n_seconds: 10 data_hint: null data_type:NIX_SYSTEM
enabled: true tcp_address: 0.0.0.0:30000 connection_timeout_sec: 60 - syslog: common: batch_n_bytes: 1048576 batch_n_seconds: 10 data_hint: null data_type:WINEVTLOG
enabled: true tcp_address: 0.0.0.0:30001 connection_timeout_sec: 60
Configure arbitrary labels
Labels are used to attach arbitrary metadata to logs using key and value pairs. Labels can be configured for an entire forwarder or within a specific collector of a forwarder. If both are provided, the labels are merged with the collector's keys taking precedence over the forwarder's keys if the keys overlap.
Example configuration: arbitrary labels
In the following forwarder configuration, the 'foo=bar' and 'meow=mix' key and
value pairs are both attached to WINEVTLOG
logs, and the 'foo=baz' and
'meow=mix' key and value pairs are attached to the NIX_SYSTEM
logs.
metadata: labels: foo: bar meow: mix collectors: syslog: common: metadata: labels: foo: baz meow: mix batch_n_bytes: 1048576 batch_n_seconds: 10 data_hint: null data_type:NIX_SYSTEM
enabled: true tcp_address: 0.0.0.0:30000 connection_timeout_sec: 60 syslog: common: batch_n_bytes: 1048576 batch_n_seconds: 10 data_hint: null data_type:WINEVTLOG
enabled: true tcp_address: 0.0.0.0:30001 connection_timeout_sec: 60
Configure namespaces
Use namespace labels to identify logs from distinct network segments and deconflict overlapping IP addresses. You can configure a namespace label for an entire forwarder or within a specific collector of the forwarder. If both are included, the specific collector's namespace takes precedence.
Any namespace configured for the forwarder appears with the associated assets in the Google Security Operations user interface. You can also search for namespaces using the Google Security Operations Search feature.
Learn more about how to view namespaces in the Google Security Operations user interface.
Example configuration: namespaces
In the following forwarder configuration, the WINEVTLOG
logs are
attached to the FORWARDER namespace and NIX_SYSTEM
logs are
attached to the CORPORATE namespace.
metadata: namespace: FORWARDER collectors: - syslog: common: metadata: namespace: CORPORATE batch_n_bytes: 1048576 batch_n_seconds: 10 data_hint: null data_type:NIX_SYSTEM
enabled: true tcp_address: 0.0.0.0:30000 connection_timeout_sec: 60 - syslog: common: batch_n_bytes: 1048576 batch_n_seconds: 10 data_hint: null data_type:WINEVTLOG
enabled: true tcp_address: 0.0.0.0:30001 connection_timeout_sec: 60
Configure load balancing and high availability options
The Google Security Operations forwarder for Linux can be deployed in an environment where a Layer 4 load balancer is installed between the data source and forwarder instances. This allows a customer to distribute the log collection across multiple forwarders or send logs to a different forwarder if one fails. This feature is supported only with the syslog collection type.
The Linux forwarder includes a built-in HTTP server that responds to HTTP health checks from the load balancer. The HTTP server also helps ensure that logs are not lost during startup or shutdown of a forwarder.
Configure the HTTP server, load balancing, and high availability options under the server section of the forwarder configuration file. These options support setting timeout durations and status codes returned in response to health checks received in container scheduler and orchestration-based deployments, as well as from conventional load balancers.
Use the following URL paths for health, readiness, and liveness checks.
The <host:port>
values are defined in the forwarder configuration.
- http://
<host:port>
/meta/available: liveness checks for container schedulers or orchestrators. - http://
<host:port>
/meta/ready: readiness checks and conventional load balancer health checks.
The following forwarder configuration is an example for load balancing and high availability:
collectors: - syslog: common: batch_n_bytes: 1048576 batch_n_seconds: 10 data_hint: null data_type:NIX_SYSTEM
enabled: true tcp_address: 0.0.0.0:30000 connection_timeout_sec: 60 - syslog: common: batch_n_bytes: 1048576 batch_n_seconds: 10 data_hint: null data_type:WINEVTLOG
enabled: true tcp_address: 0.0.0.0:30001 connection_timeout_sec: 60 server: graceful_timeout: 15s drain_timeout: 10s http: port: 8080 host: 0.0.0.0 read_timeout: 3s read_header_timeout: 3s write_timeout: 3s idle_timeout: 3s routes: - meta: available_status: 204 ready_status: 204 unready_status: 503
Configuration path | Description |
---|---|
server : graceful_timeout | The amount of time the forwarder returns a bad readiness/health check and still accepts new connections. This is also the time to wait between receiving a signal to stop and actually beginning the shutdown of the server itself. This allows the load balancer time to remove the forwarder from the pool. |
server : drain_timeout | The amount of time the forwarder waits for active connections to successfully close on their own before being closed by the server. |
server : http : port | The port number that the HTTP server listens on for health checks from the load balancer. Must be between 1024-65535. |
server : http : host | The IP address, or hostname that can be resolved to IP addresses, that the server should listen to. If empty, the default value is local system (0.0.0.0). |
server : http : read_timeout | Used to tune the HTTP server. Typically, does not need to be changed from the default setting. The maximum amount of time allowed to read the entire request, both the header and the body. You can set both read_timeout and read_header_timeout. |
server : http : read_header_timeout | Used to tune the HTTP server. Typically, does not need to be changed from the default setting. The maximum amount of time allowed to read request headers. The connection's read the deadline is reset after reading the header. |
server : http : write_timeout | Used to tune the HTTP server. Typically, does not need to be changed from the default setting. The maximum amount of time allowed to send a response. It is reset when a new request header is read. |
server : http : idle_timeout | Used to tune the HTTP server. Typically, does not need to be changed from the default setting. The maximum amount of time to wait for the next request when idle connections are enabled. If idle_timeout is zero, the value of read_timeout is used. If both are zero, the read_header_timeout is used. |
routes : meta : ready_status | The status code the forwarder returns when it is ready to accept the traffic
in either of the following situations:
|
routes : meta : unready_status | The status code the forwarder returns when it is not ready to accept traffic. |
routes : meta : available_status | The status code the forwarder returns when a liveness check is received and the forwarder is available. Container schedulers or orchestrators often send liveness checks. |
Frequently asked questions
How do I update my forwarder?
The Linux forwarder is constantly updated through a shell script in the Docker image. To update the Docker image, run the forwarder.
What is a Docker container?
Docker containers are like virtual machines that provide additional security, isolation and resource management.
Virtual Machines—have both a privileged space (linux kernel) and a user space (everything you interact with: libc, python, ls, tcpdump, and so on).
Containers—have only a user space (everything you interact with: libc, python, ls, tcpdump, and so on) and rely on the host's privilege space.
Why distribute Google Security Operations forwarder using a container?
- Better security through isolation:
- Customer environment and requirements don't affect Google Security Operations forwarder.
- Google Security Operations forwarder environment and requirements don't affect the customer.
- Container distribution mechanism already exists and can be private and separate for Google Cloud and customers. https://cloud.google.com/container-registry/
Do you need to learn advanced Docker commands?
- Google Security Operations forwarder uses a single container, so there is no need to learn about Swarm, orchestration, or other advanced Docker concepts or commands.