After you install Cortex XDR agent for Linux, the agent operates transparently in the background as a system process. The Cortex XDR agent communicates with the server at a fixed 5-minute heartbeat interval to send status information and retrieve the latest security policy. Typically, it is not necessary to interact with the agent; however, to perform common actions, such as initiating a manual check in with Cortex XDR, you can use the command-line utility (also available for Mac and Windows) named Cytool. Cytool is available in the `/opt/traps/bin/cytool` directory and must be run as root or with root permissions.
1. Display the Cytool help.
From the Linux server, run the **`cytool`** command without any arguments or with **`-h`** or **`--help`** options.
```screen
root@ubuntu:~$ /opt/traps/bin/cytool
Usage: cytool<options>
cytool - Support tool
Options:
-h --help Display help information.
enum List processes protected by Cortex XDR.
startup query List startup status for Cortex XDR endpoint agent(s) and daemon(s).
startup <enable | disable> <process_name | all> Enable/Disable agent(s) and daemon(s) after reboot.
runtime query List runtime status for agent(s), daemon(s) and kernel extensions.
runtime <start | stop> <process_name | all> Start/Stop agent(s), daemon(s) and kernel extensions immediately.
persist list Display list of persistent databases.
persist export <db_name | db_path> Export database(s) to the file(s) in JSON format.
persist import <db_name | db_path> <file_name> Import data into the database from the given JSON file.
persist print <db_name | db_path> [csv] Print database to the command prompt.
log <log_level> <process_name | all> Set log level for the desired process.
log collect Generate support file archive.
dump <enable | disable | restore> Enable/Disable dump generation or restore policy settings.
checkin Initiate Check In Now (send heartbeat to ESM).
```
Follow the usage guidelines to run additional Cytool commands.
2. List processes protected by the agent.
Enter the **`cytool enum`** command.
```screen
root@ubuntu:~$ cytool
enum
-----------------------------------
Cortex XDR list of protected processes:
-----------------------------------
PID CMD UID
1098 /usr/sbin/cron -f 0
1131 /usr/sbin/rsyslogd -n 104
```
To view processes for all users including those initiated by the operating system, specify the **`/a`** option.
<div data-gb-custom-block data-tag="hint" data-style="info" class="hint hint-info"><h3>Note</h3><p>If you change the action mode for protected processes in the Exploit Security Profile in Cortex XDR, you must restart the protected processes for the security policy to be enforced on the processes and its forked processes, and only then you will see them on this list.</p></div>
3. Start or stop Cortex XDR agent daemons.
The agent comprises the pmd, dypd, analyzerd and lted processes. pmd is the main process and it automatically starts/stops dypd, analyzerd and lted. To start or stop all daemons, enter either the **`cytool runtime [start | stop] all`** command or the **`cytool startup [enable | disable] all`** command. The behavior of both commands changes both the current running state and the startup registration status of the daemons when the server boots.
For example:
```screen
root@ubuntu16:~# /opt/traps/bin/cytool runtime stop all
Name PID User Status Command
pmd N/A N/A STOPPED N/A
analyzerd N/A N/A STOPPED N/A
dypd N/A N/A STOPPED N/A
lted N/A N/A STOPPED N/A
root@ubuntu16:~# /opt/traps/bin/cytool runtime start all
Name PID User Status Command
pmd 20798 root Running /opt/traps/bin/pmd
analyzerd 21027 cortexu+ Running /opt/traps/analyzerd/analyzerd 109 111 113
dypd 20999 root Running /opt/traps/bin/dypd -a -- 99
lted 20982 cortexu+ Running /opt/traps/ltee/lted -type 2 -config ltee_decryptor.json
```
4. View the Cortex XDR agent security policy.
The agent stores policy and security event information such as the list of trusted signers, local verdicts, and one-time actions in local databases in the `/opt/traps/persist/` directory. To troubleshoot policy issues and security events, you can use Cytool to import, export, and view information stored in the local database.
To view a list of all local databases, use the **`cytool persist list`** command.
```screen
root@ubuntu:~$ /opt/traps/bin/cytool
persist list
Persistent database list:
post_detection.db Database of post-detection candidates
agent_actions.db Database of one time actions
cloud_frontend.db Database of Cloud frontend settings
hashes_lru.dbLeastrecently used verdicts database
cloud_reports.db Database of Cloud reports
hashes.db Database of the verdicts received from WildFire
esm_frontend.db Database of ESM frontend settings
policy.db Policy database
fvhash.db Database of blacklisted fvhashes
trusted_signers.db Database of trusted signers
hash_paths.db Database of file paths
hash_override.db Database of hashes override (Admin exeptions)
esm_reports.db Database of ESM reports
security_events.db Database of security events (preventions)
file_upload.db Database of files being uploaded to ESM
hashes_retransmit.db Database of hashes to be retransmitted
agent_settings.db Database of agent settings
```
To view the records of a database, use the **`cytool persistprint [`**_**`<database_name>`**_**`|`**_**`<database_path>`**_**`]`** command where you specify either the name of database (see the **`cytoolpersist list`** command) or the path to the database. Or, to export the records of a database to a JSON file, use the **`cytoolpersist export [`**_**`<database_name>`**_**`|`**_**`<database_path>`**_**`]`** command. For example:
```screen
root@ubuntu:~$ /opt/traps/bin/cytool
persist print security_events.db
Database security_events:
persistence::DB: /opt/traps/persist/security_events.db: Open
persistence::DB: /opt/traps/persist/security_events.db: Open: IO error: lock /opt/traps/persist/security_events.db/LOCK: Resource temporarily unavailable
3c34dcc1-bc37-ffef-ed55-f5512df05884,
Prevention ID: 3c34dcc1-bc37-ffef-ed55-f5512df05884
Time: 2018-05-02T10:31:51Z
Timezone offset (min): 240
Module ID (CyveraComponent): 277
Module status (CyStatus): 0xC0400015
Blocked: false
Source process ID: 14818
Source process terminated: true
Source process command line: /root/Desktop/Linux_testers/ROP/lighttpd system 0
Source process file index: 0
Target process ID: 0
Target process terminated: false
Target process command line:
Target process file index: 0
User ID: 0
User name:
Cortex XDR version: 7.3.0.0
OS name: Linux
OS version: Red Hat Enterprise Linux Server release 6.9 (Santiago)
Machine name: Saar_redhat64x64
Dump path: /opt/traps/forensics/3c34dcc1-bc37-ffef-ed55-f5512df05884/
Content version: 17-3805
IP Address: 10.200.0.55
Verdict (WildFire/Hash Control): 0
1 Files:
Name: lighttpd
Path: /root/Desktop/Linux_testers/ROP
Size: 0
Hash: 8630c9e57ca58fb7966c80525c36f572416e0a8db617b8a43c946d4fa966a71c
Version:
Publisher:
Quarantine ID:
Signers: ''
------------------------------------------------
---------- END Security Event Files ----------
root@ubuntu:~$ /opt/traps/bin/cytool persist export security_events.db
persistence::DB: /opt/traps/persist/security_events.db: Open
-rw-r--r-- 1 ubuntu root 25824 Jan 2 18:10 /home/ubuntu/traps/cytool/security_events.db_18.10.04.427_02.01.2018.json
```
To add records to the database, use the **`cytoolpersist import [`**_**`<database_name>`**_**`|`**_**`<database_path>`**_**` ]`` `` `**_**`<input_filename>`**_ command where _**`<input_filename>`**_ is a JSON file.
5. Collect logs.
Use the **` cytool log set_level`` `` `**_**`<log_level>`**_**` `` ``[ `**_**`<process_name>`**_**` `` ``|all] `** command to change the log level of an agent component where:
* _**`<log_level>`**_ is an integer value corresponding to the log level:
* 1—Fatal
* 2—Critical
* 3—Error
* 4—Warning
* 5—Notice
* 6—Information
* 7—Debug
* 8—Trace
* _**`<process_name>`**_ is the Cortex XDR agent component: **`trapsd`**, **`authorized`**, **`pmd`**, or **`dypd`**.
Then use the **`cytool log collect`** command to collect all logs in a TGZ file.
```screen
root@ubuntu:~$ /opt/traps/bin/cytool log
1 trapsd
root@ubuntu:~$ /opt/traps/bin/cytool log collect
-rw-r--r-- 1 root root 1651939 Dec 30 20:33 /tmp/Traps_log_2017-12-30_20-33-22/Traps_log_2017-12-30_20-33-22.tgz
```
6. Manually initiate a check in with the server.
Use the **`cytool checkin`** command to initiate the manual check-in. To verify the status of the check-in on Cortex XDR, view the **LAST SEEN** date from the additional details view of an endpoint on the **Endpoints** page.
7. Configure proxy communication.
<div data-gb-custom-block data-tag="hint" data-style="info" class="hint hint-info"><h3>Note</h3><p>To configure system-wide proxy settings for your endpoints, follow the instructions below. You can also <a href="install-the-cortex-xdr-agent-for-linux">configure a Cortex XDR agent specific proxy</a>.</p></div>
If defined, the agent uses the proxy settings defined in the system environment in `/etc/environment`. If proxy settings are not defined, you can add the proxy server to the system environment by specifying the following setting in the `environment` file:
**`https_proxy="http://`**_**`<proxyserver>`**_**`:`**_**`<port>`**_**`"`**
where:
* _**`<proxyserver>`**_ is the IP address of the proxy server
* _**`<port>`**_ is the port number used for proxy communication.
For example: **`https_proxy="http://10.196.20.244:8080"`**
8. View the version of the Cortex XDR agent.
To view the version of the agent on the Linux server, open or read the `version.txt` file in the `/opt/traps/` directory. For example:
```screen
root@ubuntu:~$ cat /opt/traps/version.txt
traps_linux-6.1.0.1040
ce1707dadbbb67effb7bf08cd4edee60d9508377
```