Cisco Cisco Expressway Maintenance Manual
xStatus Options
To add a new option key to your system:
xConfiguration Option [1..64] Key
Note:
when using the CLI to add an extra option key, you can use any unused option index. If you chose an existing
option index, that option will be overwritten and the extra functionality provided by that option key will no longer exist.
To see which indexes are currently in use, type
To see which indexes are currently in use, type
xConfiguration option
.
About Security Certificates
For extra security, you may want to have the Expressway communicate with other systems (such as LDAP servers,
neighbor Expressways, or clients such as SIP endpoints and web browsers) using TLS encryption.
neighbor Expressways, or clients such as SIP endpoints and web browsers) using TLS encryption.
For this to work successfully in a connection between a client and server:
■
The server must have a certificate installed that verifies its identity. This certificate must be signed by a
Certificate Authority (CA).
Certificate Authority (CA).
■
The client must trust the CA that signed the certificate used by the server.
The Expressway allows you to install appropriate files so that it can act as either a client or a server in connections
using TLS. The Expressway can also authenticate client connections (typically from a web browser) over HTTPS. You
can also upload certificate revocation lists (CRLs) for the CAs used to verify LDAP server and HTTPS client
certificates.
using TLS. The Expressway can also authenticate client connections (typically from a web browser) over HTTPS. You
can also upload certificate revocation lists (CRLs) for the CAs used to verify LDAP server and HTTPS client
certificates.
The Expressway can generate server certificate signing requests (CSRs). This removes the need to use an external
mechanism to generate and obtain certificate requests.
mechanism to generate and obtain certificate requests.
For secure communications (HTTPS and SIP/TLS) we recommend that you replace the Expressway default certificate
with a certificate generated by a trusted certificate authority.
with a certificate generated by a trusted certificate authority.
Note that in connections:
■
to an endpoint, the Expressway acts as the TLS server
■
to an LDAP server , the Expressway is a client
■
between two Expressway systems, either Expressway may be the client with the other Expressway being the
TLS server
TLS server
■
via HTTPS, the web browser is the client and the Expressway is the server
TLS can be difficult to configure. For example, when using it with an LDAP server we recommend that you confirm
that your system is working correctly before you attempt to secure the connection with TLS. You are also
recommended to use a third party LDAP browser to verify that your LDAP server is correctly configured to use TLS.
that your system is working correctly before you attempt to secure the connection with TLS. You are also
recommended to use a third party LDAP browser to verify that your LDAP server is correctly configured to use TLS.
Note:
be careful not to allow your CA certificates or CRLs to expire as this may cause certificates signed by those CAs
to be rejected.
Certificate and CRL files can only be managed via the web interface. They cannot be installed using the CLI.
.
Managing the Trusted CA Certificate List
The Trusted CA certificate page (Maintenance > Security certificates > Trusted CA certificate) allows you to
manage the list of certificates for the Certificate Authorities (CAs) trusted by this Expressway. When a TLS
connection to Expressway mandates certificate verification, the certificate presented to the Expressway must be
signed by a trusted CA in this list and there must be a full chain of trust (intermediate CAs) to the root CA.
manage the list of certificates for the Certificate Authorities (CAs) trusted by this Expressway. When a TLS
connection to Expressway mandates certificate verification, the certificate presented to the Expressway must be
signed by a trusted CA in this list and there must be a full chain of trust (intermediate CAs) to the root CA.
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Cisco Expressway Administrator Guide
Maintenance