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Click Generate. Finally, click the certificate name to edit it, select the Certificate for Secure Syslog check box, and click OK. For more information about generating a certificate, see the vendor documentation.
Now, you need to export the certificates. In Device → Certificate Management → Certificates → Device Certificates., select the RootCA certificate and click Export. Choose PEM as the format. Do the same for the SyslogCert certificate.
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For more information about exporting certificates, see the vendor documentation.
Copy the Palo Alto certificates to the Devo relay/stunnel machine
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For more information about syslog forwarding, see the vendor documentation.