Cisco Cisco Web Security Appliance S170 사용자 가이드
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AsyncOS 9.1.1 for Cisco Web Security Appliances User Guide
Appendix A Troubleshooting
Identity Services Engine Problems
Conditions and Restrictions for Exceptions to Blocking for Embedded and
Referred Content
Referred Content
Referrer-based exceptions are supported only in Access policies. To use this feature with HTTPS traffic,
before defining exceptions in Access policies, you must configure HTTPS decryption of the URL
Categories that you will select for exception. However, this feature will not work under certain conditions:
before defining exceptions in Access policies, you must configure HTTPS decryption of the URL
Categories that you will select for exception. However, this feature will not work under certain conditions:
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If the connection is tunneled and HTTPS decryption is not enabled, this feature will not work for
requests going to HTTPS sites.
requests going to HTTPS sites.
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According to RFC 2616, a browser client could have a toggle switch for browsing
openly/anonymously, which would respectively enable/disable the sending of Referer and from
information. The feature is exclusively dependent on the Referer header, and turning off sending
them would cause our feature not to work.
openly/anonymously, which would respectively enable/disable the sending of Referer and from
information. The feature is exclusively dependent on the Referer header, and turning off sending
them would cause our feature not to work.
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According to RFC 2616, clients should not include a Referer header field in a (non-secure) HTTP
request if the referring page was transferred with a secure protocol. So, any request from an
HTTPS-based site to an HTTP-based site would not have the Referer header, causing this feature to
not work as expected.
request if the referring page was transferred with a secure protocol. So, any request from an
HTTPS-based site to an HTTP-based site would not have the Referer header, causing this feature to
not work as expected.
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When a Decryption policy is set up such that when a custom category matches the Decryption policy
and the action is set to Drop, any incoming request for that category will be dropped, and no
bypassing will be done.
and the action is set to Drop, any incoming request for that category will be dropped, and no
bypassing will be done.
Alert: Problem with Security Certificate
Typically, the root certificate information you generate or upload in the appliance is not listed as a trusted
root certificate authority in client applications. By default in most web browsers, when users send
HTTPS requests, they will see a warning message from the client application informing them that there
is a problem with the website’s security certificate. Usually, the error message says that the website’s
security certificate was not issued by a trusted certificate authority or the website was certified by an
unknown authority. Some other client applications do not show this warning message to users nor allow
users to accept the unrecognized certificate.
root certificate authority in client applications. By default in most web browsers, when users send
HTTPS requests, they will see a warning message from the client application informing them that there
is a problem with the website’s security certificate. Usually, the error message says that the website’s
security certificate was not issued by a trusted certificate authority or the website was certified by an
unknown authority. Some other client applications do not show this warning message to users nor allow
users to accept the unrecognized certificate.
Note
Mozilla Firefox browsers: The certificate you upload must contain
“basicConstraints=CA:TRUE” to work with Mozilla Firefox browsers. This constraint allows
Firefox to recognize the root certificate as a trusted root authority.
“basicConstraints=CA:TRUE” to work with Mozilla Firefox browsers. This constraint allows
Firefox to recognize the root certificate as a trusted root authority.
Identity Services Engine Problems
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Tools for Troubleshooting ISE Issues
The following can be useful when troubleshooting ISE-related issues: