8.1. Diagnostic Pack¶
The diagnostic package is an archive generated on ASGARD server to help Nextron support engineers with the debugging of your problem. It contains the system configuration and log data of an ASGARD instance.
You can generate a Diagnostic Package in
Systems Status > Tab: Logs > Diagnostics Package.
The package can have a size that cannot be shared via Email. In this case you can either
- ask us for an upload link (secure file sharing) or
- remove big log files from the package (e.g. the file
./var/lib/nextron/asgard2/log/agent-access.logis often responsible for 97% of the package size)
8.2. Agent Debugging¶
8.2.1. Internal Agent Debugging¶
Edit the file
asgard2-agent.yaml and set the value of
to true. The file can be found in
/var/lib/asgard2-agent/ for Windows and Linux/macOS, respectively.
After making these changes, restart the ASGARD service. You can then
find log entries and possible error messages in the file
in the same directory as the configuration file.
Note: The value is set to
false by default, because the agent
doesn't rotate or compress these logs. Leaving that value on
could cause that file to grow very big and use a significant amount
of disk space. We recommend resetting it after the debugging session.
8.2.2. Go Debug Logging¶
On Windows, open the cmd.exe as Administrator. Set some environment variables.
C:\Windows\system32>set GRPC_GO_LOG_SEVERITY_LEVEL=info C:\Windows\system32>set GODEBUG=http2debug=2
Navigate into the agent's program directory and start it to see all output messages.
C:\Windows\system32>sc stop asgard2-agent C:\Windows\system32>cd C:\Windows\system32\asgard2-agent\ C:\Windows\system32\asgard2-agent>asgard2-agent.exe
Interrupt the agent with
CTRL+C. Don't forget to start the Windows service after the debugging session.
C:\Windows\system32\asgard2-agent>sc start asgard2-agent
On Linux, open a shell as root (sudo).
nextron@asgard:~$ sudo su - [sudo] password for nextron: root@asgard:~# root@asgard:~# export GRPC_GO_LOG_SEVERITY_LEVEL=info root@asgard:~# export GODEBUG=http2debug=2
Navigate into the agent's program directory and start it to see all output messages.
root@asgard:~# systemctl stop asgard2-agent root@asgard:~# cd /var/lib/asgard2-agent/ root@asgard:/var/lib/asgard2-agent# ./asgard2-agent
Interrupt the agent with
CTRL+C. Don't forget to start the Linux service after the debugging session.
root@asgard:/var/lib/asgard2-agent# systemctl start asgard2-agent
8.2.3. Aurora Diagnostics Pack¶
If Aurora does not behave like it should, e.g. using more resources
than you expected, you can create a diagnostics pack for our support
to help in troubleshooting the issue. This can be conveniently done
using the playbook
[Default] Create and Collect Aurora Agent Diagnostics Pack (Windows).
It can be run from
Asset Management >
Response Action (Play button)
Response Control >
Add Task or if needed
as a group task. The resulting
diagnostics.zip can be downloaded
from the third step in the
Playbook Result tab of the expanded task.
8.2.4. Duplicate Assets Remediation¶
If you are seeing the
Duplicate Assets view in your
you need to fix the issue to avoid unwanted behavior of this asset. To
fix the issue, you need to uninstall the current ASGARD agent, delete the
configuration files, and redeploy a fresh copy.
- To uninstall the ASGARD agent, please follow the instructions in Uninstall ASGARD Agents.
- To delete the configuration files, make sure that the following folder is
deleted before installing a new agent:
- To install the ASGARD agent, please follow the instructions in ASGARD Agent Deployment.
It is also recommended to redeploy the ASGARD Service Controller.
- To uninstall the ASGARD Service Controller, please follow the instructions in Uninstall ASGARD Service Controller.
- To install the ASGARD Service Controller, please follow the
instructions in Service Controller Installation.
You need to wait a few minutes until the asset is connected to your ASGARD
before you continue with this step. Please note that you might need to accept the
8.3. SSL Interception¶
Using a web proxy with TLS/SSL interception will break the installation routine and shows this error:
Certificate verification failed: The certificate is NOT trusted. The certificate issuer is unknown. Could not handshake: Error in the certificate verification.
Solution: Disable TLS/SSL interception for our update servers.
Used for THOR updates:
We do not support setups in which the CA of the intercepting proxy is used on our ASGARD appliances.
8.4. Using Hostname instead of FQDN¶
The most common error is to define a simple hostname instead of a valid
FQDN during installation. This happens in cases in which no domain name
has been set in the setup step Network Configuration
This leads to a variety of different problems.
The most important problem is that ASGARD Agents that install on end systems will never be able to resolve and connect to the ASGARD server.
8.4.1. Errors that appear in these cases¶
Apr 23 12:07:12 debian10-dev/10.10.30.118 ASGARD_AGENT: Error: could not run: rpc error: code = Unavailable desc = connection error: desc = "transport: authentication handshake failed: x509: certificate is valid for wrong-fqdn, not asgard.nextron.internal"
8.4.2. How to Fix an unset or wrong FQDN¶
The FQDN is set at installation time and is composed by the hostname and the domain name. The ASGARD Agents require a resolvable FQDN to correctly operate and connect to the ASGARD Server. One of the processes which are executed at installation time include the integration of the FQDN we set during installation into our agents. If we incorrectly set the FQDN or we leave any of those values empty, the agents will fail to connect to ASGARD.
With this fix we'll set a new FQDN for the ASGARD Server, recreate the internal certificates and rebuild the agents.
The used FQDN in this manual is just an example. Please use the FQDN of your domain.
126.96.36.199. Set a valid FQDN¶
To set a valid FQDN for your ASGARD Management Center server, follow the steps below. We are assuming that your ASGARD Management Center has already a FQDN assigned via your local DNS servers and is resolvable.
Connect via SSH to the ASGARD Management Center:
user@somehost:~$ ssh email@example.com
Edit the hosts file. Please be careful with the changes in this file, as this might make your system unusable!
nextron@asgard-mc:~$ sudoedit /etc/hosts [sudo] password for nextron:
You need to change the following line (do not change the IP-Address!):
1 2 3 4 5 6 7
127.0.0.1 localhost 172.16.0.20 asgard-mc # The following lines are desirable for IPv6 capable hosts ::1 localhost ip6-localhost ip6-loopback ff02::1 ip6-allnodes ff02::2 ip6-allrouters
To this (values are examples, please change accordingly!)
1 2 3 4 5 6 7
127.0.0.1 localhost 172.16.0.20 asgard-mc.example.org asgard-mc # The following lines are desirable for IPv6 capable hosts ::1 localhost ip6-localhost ip6-loopback ff02::1 ip6-allnodes ff02::2 ip6-allrouters
If you did not set a static IP-Address for your ASGARD Management Center
server, your IP-Address in the second line of the file might be
This is due to your server using DHCP. It is advised that you are using a
static IP-Address. To change this, please see Changing the IP-Address.
You can verify if the changes worked. Run the following commands and see the difference in the output:
nextron@asgard-mc:~$ hostname --fqdn asgard-mc.example.org nextron@asgard-mc:~$ hostname asgard-mc
If the first command shows the FQDN and the second one the hostname without domain, your changes were set up correctly and you can continue to the next step.
188.8.131.52. Recreate the TLS Certificate¶
We need to recreate the TLS certificate to make the Agent communication possible again.
Create a new file which will contain the script with the fix. In this example we'll use nano as the text editor.
nextron@asgard-mc:~$ nano fix-fqdn.sh
DOMAIN variable (marked lines), make sure that the resulting
FQDN is resolvable by the endpoints on which you deploy the agent to later.
The FQDN should be identical to the value we set earlier in our
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
#!/bin/bash # VARIABLES ############################################ HOST="asgard-mc" DOMAIN="example.org" FQDN=$HOST.$DOMAIN CLIENTCERTVALIDITY=36500 ############################################ openssl req -new -newkey rsa:4096 -days 36500 -nodes -x509 -subj "/O=Nextron Systems GmbH/CN=$FQDN" -keyout /etc/nextron/asgard2/server.key -out /etc/nextron/asgard2/server.pem openssl req -newkey rsa:4096 -nodes -subj "/O=Nextron Systems GmbH/CN=$FQDN" -keyout /etc/nextron/asgard2/client-service.key -out /etc/nextron/asgard2/client-service.csr openssl x509 -req -in /etc/nextron/asgard2/client-service.csr -CA /etc/nextron/asgard2/ca.pem -CAkey /etc/nextron/asgard2/ca.key -CAcreateserial -days $CLIENTCERTVALIDITY -out /etc/nextron/asgard2/client-service.pem asgard2-repacker -host $FQDN
After changing the variables to the desired values, save the file.
nano this can be done in by pressing
CTRL + X and confirming the changes with
Give the created script execution permissions and execute it:
nextron@asgard-mc:~$ chmod +x fix-fqdn.sh nextron@asgard-mc:~$ sudo ./fix-fqdn.sh
Once the script has been executed the ASGARD service should be restarted.
nextron@asgard-mc:~$ sudo systemctl restart asgard2.service
You should now be able to reach the ASGARD Server under the new FQDN.
https://<YOUR-FQDN>:8443, which reflects the FQDN we set earlier.
You should now install the agents on the endpoints again. They should be communicating correctly back to ASGARD by now. Remember to review the network requirements section to ensure all needed ports are open to the ASGARD Management Center from your endpoints.
8.5. ASGARD Errors¶
8.5.1. ASGARD noticed that the THOR scan failed¶
In some cases THOR fails to complete its scan and ASGARD reports the following error.
ASGARD noticed that the THOR scan failed could not remove temp directory: remove C:\Windows\Temp\asgard2-agent\12fa35a6762a\thor\signatures\sigma\windows\file_event_win_webshell_creation_detect.yms: The process cannot access the file because it is being used by another process. exit status 1 (scan result does not exist)
The most likely reason for this error is an Antivirus interaction. The Antivirus killed the THOR process and still holds a handle to one of the signature files. The "THOR Launcher" can only report that the process was terminated and that it isn't able to remove all files because the Antivirus process still has that open handle on the file.
Configure an Antivirus exclusion for THOR. See Antivirus or EDR Exclusions for more details.
8.6. Resetting TLS/SSL Certificates¶
8.6.1. Web GUI: Regenerate the Self-Signed Certificate¶
ASGARD ships with a self-signed certificate for its web interface that expires after 182 days. If you do not use your own CA infrastructure and want to renew the certificate or want to revert from a broken state, you can recreate a self-signed certificate. To do so log in using SSH and execute:
nextron@asgard:~$ sudo openssl req -new -newkey rsa:4096 -days 182 -nodes -x509 -subj "/O=Nextron Systems GmbH/CN=$(hostname --fqdn)" -keyout /etc/nextron/asgard2/server.key -out /etc/nextron/asgard2/server.pem
You need to restart ASGARD in order for the changes to take effect.
nextron@asgard:~$ sudo systemctl restart asgard2.service
8.6.2. Regenerate ASGARD Server Certificate Agent Communication¶
In order to reset the certificate that ASGARD uses to communicate with the agents, use the following commands. The agent should immediately trust the new certificate, as it was generated using the CA they already trust.
nextron@asgard:~$ su asgard2 -s /bin/sh <<'EOF' openssl req -new -nodes -subj "/O=Nextron Systems GmbH/CN=ASGARD Management Center" -key /etc/nextron/asgard2/client-service.key -out /etc/nextron/asgard2/client-service.csr openssl x509 -req -in /etc/nextron/asgard2/client-service.csr -CA /etc/nextron/asgard2/ca.pem -CAkey /etc/nextron/asgard2/ca.key -CAcreateserial -days 36500 -out /etc/nextron/asgard2/client-service.pem -extfile /etc/nextron/asgard2/server_cert_ext.cnf EOF
8.7. Admin User Password Reset¶
If you've lost the password of the local
admin user (Web GUI) but
still have access the system via SSH, you can reset it via command
line using the following command.
nextron@asgard:~$ sudo mysql asgard -e "UPDATE users SET password = 'YmIc6P_6jdbeEL0HY4xIcpYstmM' WHERE name = 'admin';"
This resets the password to
admin. You should then change that password immediately.
8.8. Reset Two Factor Authentication for a specific User¶
If you or another user lost their second factor (2FA) to log into the ASGARD Web UI, you have to reset the users MFA Settings. If you cannot access the Web UI, use the Command Line method.
There are two possible ways to reset
Two Factor Authentication for a specific user.
We recommend to use the first option via the WebUI.
8.8.1. Using the Web UI¶
Log into ASGARDs Web UI as a user with administrative privileges.
Authentication > Users and edit the user
you want to reset 2FA for. On the bottom of the popup you will see that
2FA option is enabled. Disable the option and click
(Leave everything else as it is; do not fill in a new password if not
After you edited the user, the
Two Factor Authentication will be disabled
and the user can log into ASGARD without 2FA.
8.8.2. Using the Command Line Interface¶
This method needs SSH access to ASGARD.
Log into your ASGARD via SSH. You can reset the users MFA Settings with
the following command (in this example we assume that the user is called
nextron@asgard:~$ sudo mysql asgard --execute "UPDATE users SET tfa_valid = 0 WHERE name = 'john';"
This will disable the 2FA settings directly in the database. Please make sure the command and especially the username is correct.
If you don't know the exact username for a user, you can use the following command
to get all the usernames and the 2FA status from ASGARD (if
tfa_valid has a value
1, this means the user has Two Factor Authentication enabled).
nextron@asgard:~$ sudo mysql asgard --execute "select name,tfa_valid from users;" +----------+-----------+ | name | tfa_valid | +----------+-----------+ | admin | 1 | | john | 0 | | rickroll | 1 | +----------+-----------+
This command will also allow you to verify if the
UPDATE command was successful (
tfa_valid should be
8.9. Scheduled Scans do not run at the correct time¶
In some cases the timezone during the installation of the server image might not be correct. To see if you have this problem in your current installation, please log into your server and execute the following command:
nextron@asgard:~$ timedatectl Local time: Mon 2022-10-24 09:52:03 BST Universal time: Mon 2022-10-24 08:52:03 UTC RTC time: Mon 2022-10-24 08:52:04 Time zone: Europe/London (BST, +0100) System clock synchronized: no NTP service: inactive RTC in local TZ: no
If you see that the Time zone is incorrect, follow the next steps to correct it.
List all the timezones with
timedatectl list-timezones. If you want
to search for a specific Country/City, you can use grep, e.g.
timedatectl list-timezones | grep Prague.
Now that you have the correct timezone you can set it the following way:
nextron@asgard:~$ sudo timedatectl set-timezone Europe/Prague nextron@asgard:~$ timedatectl Local time: Mon 2022-10-24 10:56:45 CEST Universal time: Mon 2022-10-24 08:56:45 UTC RTC time: Mon 2022-10-24 08:56:46 Time zone: Europe/Prague (CEST, +0200) System clock synchronized: no NTP service: inactive RTC in local TZ: no
Please reboot the system after the changes have been made.
This might cause problems with existing Scheduled Scans!
8.10. Aurora is generating too many False Positives¶
In some environments, Aurora might generate a high amount of False Positives. This should never be the case, since Aurora should only alert on very few and mostly important findings. Most likely a rule is matching on the environment and generates too many false positives. To circumvent this, you can disable the rule and set a filter later on. For Tuning, please see False Positive Tuning of Sigma Rules.