Cisco Cisco Expressway
Generating a certificate signing request (CSR)
A CSR contains the identity information about the owner of a private key. It can be passed to a third-party or
internal certification authority for generating a signed certificate, or it can be used in conjunction with an
application such as Microsoft Certification Authority or OpenSSL.
internal certification authority for generating a signed certificate, or it can be used in conjunction with an
application such as Microsoft Certification Authority or OpenSSL.
Creating a CSR using Expressway
The Expressway can generate server certificate signing requests. This removes the need to use an external
mechanism to generate and obtain certificate requests.
mechanism to generate and obtain certificate requests.
To generate a CSR:
1. Go to
Maintenance > Security certificates > Server certificate
.
2. Click Generate CSR to go to the
Generate CSR
page.
3. Enter the required properties for the certificate.
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if your Expressway is part of a cluster.
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if this Expressway is part of a Unified
Communications solution.
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The certificate request includes automatically the public key that will be used in the certificate, and the
client and server authentication Enhanced Key Usage (EKU) extension.
client and server authentication Enhanced Key Usage (EKU) extension.
4. Click Generate CSR. The system will produce a signing request and an associated private key.
Note that the private key is stored securely on the Expressway and cannot be viewed or downloaded.
You must never disclose your private key, not even to the certificate authority.
You must never disclose your private key, not even to the certificate authority.
5. You are returned to the
Server certificate
page. From here you can:
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Download the request to your local file system so that it can be sent to a certificate authority. You are
prompted to save the file (the exact wording depends on your browser).
prompted to save the file (the exact wording depends on your browser).
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View the current request (click Show (decoded) to view it in a human-readable form, or click Show
(PEM file) to view the file in its raw format).
(PEM file) to view the file in its raw format).
Note that only one signing request can be in progress at any one time. This is because the Expressway has
to keep track of the private key file associated with the current request. To discard the current request and
start a new request, click Discard CSR.
to keep track of the private key file associated with the current request. To discard the current request and
start a new request, click Discard CSR.
You must now authorize the request and generate a signed PEM certificate file. You can pass it to a third-
party or internal certification authority, or use it in conjunction with an application such as Microsoft
Certification Authority (see
party or internal certification authority, or use it in conjunction with an application such as Microsoft
Certification Authority (see
When the signed server certificate is received back from the certificate authority, it must be uploaded to the
Expressway as described in
Expressway as described in
Server certificates and clustered systems
When a CSR is generated, a single request and private key combination is generated for that peer only.
If you have a cluster of Expressways, you must generate a separate signing request on each peer. Those
requests must then be sent to the certificate authority and the returned server certificates uploaded to each
relevant peer.
requests must then be sent to the certificate authority and the returned server certificates uploaded to each
relevant peer.
You must ensure that the correct server certificate is uploaded to the appropriate peer, otherwise the stored
private key on each peer will not correspond to the uploaded certificate.
private key on each peer will not correspond to the uploaded certificate.
Cisco Expressway Certificate Creation and Use
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Generating a certificate signing request (CSR)