NMC: Installation Fails with Error "Unable to Verify Authentication Server's Hostname or Port"
Summary: NetWorker Management Console (NMC) installation fails on a Windows host with error: "Unable to verify Authentication Server's hostname or port."
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Symptoms
- The NetWorker Management Console (NMC) installation fails on a Windows host with an Authentication failure message.
Figure 1: Authentication failure message appears during NMC installation on Windows.
- The NMC server is installed on a Windows host separate from the NetWorker server.
- The NetWorker authentication service is up and running.
- Port 9090 is open.
nsrports -t NetWorker_ServerName -p 9090
Cause
The NMC installation negotiates with the NetWorker authentication service over TLS earlier than version 1.2.
NOTE: See Additional Information section for instructions on validating TLS handshake between NetWorker server and NMC server.
Resolution
Perform the following on the NetWorker server:
- Make a backup copy of:
C:\Program Files\EMC NetWorker\nsr\authc-server\tomcat\conf\server.xml.
- Edit the
server.xmlfile and look for the string.
NetWorker 19.12 (and Earlier) Example:
sslEnabledProtocols="TLSv1.2"
Networker 19.13 (and later) Example:
SSLHostConfig protocols="TLSv1.2"Change the value oof the protocols string to:
"TLSv1.2, TLSv1.1, TLSv1"
NOTE: These changes are temporary and are only being done to complete the NMC installation. They can be reverted once the NMC installation has been completed.
- Save the changes to the file.
- Restart the NetWorker service.
net stop nsrd net start nsrd
- Install NetWorker and NMC on the NMC server. This time the prompt to install the certificate should appear.
NOTE: If you still do not see the option to install the certificate, the issue may be due to a mismatch between the Ciphers advertised by the Authc server OS and the ones used by your NetWorker version's Authc Ciphers. See: NetWorker: NMC server install fails on Windows Host "Unable to verify Authentication Server's Hostame and or Port". - Add the certificate to the Root Trusted certificate list.
- Click View Certificate.
- From the Certificate, click Install Certificate.
- Select Local Machine and click Next.
- Select Place all certificates in the following store, then click Browse.
- Select Trusted Root Certification Authorities, then click OK.
- On the Certificate Install Wizard, click Next.
- Click Finish.
- You should receive a pop-up stating "The import was successful," click OK.
- From the Certificate window, click OK.
- From the Security Alert window, click Yes.
- Continue until the installation completes.
After the installation finishes, revert to the original copy of server.xml. A NetWorker service restart is required for the changes to take effect.
Additional Information
Related Article: NMC install fails on Windows Host "Unable to verify Authentication Server's Hostname and/or Port"
TLS validation:
The following can be run in a PowerShell prompt on the NMC server, replace the AUTHC_SERVERNAME with your AUTHC server address.
$server = "AUTHC_SERVERNAME"
$port = 9090
$tcp = [System.Net.Sockets.TcpClient]::new()
$tcp.Connect($server, $port)
$ssl = [System.Net.Security.SslStream]::new(
$tcp.GetStream(),
$false,
{ param($sender,$cert,$chain,$errors) $true }
)
try {
$ssl.AuthenticateAsClient($server)
"=== Protocol ==="
$ssl.SslProtocol
"=== Cipher ==="
"$($ssl.CipherAlgorithm) ($($ssl.CipherStrength)-bit)"
"=== Certificate Chain (PEM) ==="
# Build the chain from the remote leaf certificate
$remoteCert = [System.Security.Cryptography.X509Certificates.X509Certificate2]::new($ssl.RemoteCertificate)
$xchain = [System.Security.Cryptography.X509Certificates.X509Chain]::new()
$null = $xchain.Build($remoteCert)
$i = 0
foreach ($elem in $xchain.ChainElements) {
$i++
$c = $elem.Certificate
"----- Certificate $i -----"
"Subject : $($c.Subject)"
"Issuer : $($c.Issuer)"
"NotBefore: $($c.NotBefore)"
"NotAfter : $($c.NotAfter)"
""
}
}
finally {
$ssl.Dispose()
$tcp.Dispose()
}
Example:
PS C:\Users\Administrator.NETWORKER> $server = "win-srvr02.networker.lan"
PS C:\Users\Administrator.NETWORKER> $port = 9090
PS C:\Users\Administrator.NETWORKER>
PS C:\Users\Administrator.NETWORKER> $tcp = [System.Net.Sockets.TcpClient]::new()
PS C:\Users\Administrator.NETWORKER> $tcp.Connect($server, $port)
PS C:\Users\Administrator.NETWORKER> $ssl = [System.Net.Security.SslStream]::new(
>> $tcp.GetStream(),
>> $false,
>> { param($sender,$cert,$chain,$errors) $true }
>> )
PS C:\Users\Administrator.NETWORKER>
PS C:\Users\Administrator.NETWORKER> try {
>> $ssl.AuthenticateAsClient($server)
>> "=== Protocol ==="
>> $ssl.SslProtocol
>> "=== Cipher ==="
>> "$($ssl.CipherAlgorithm) ($($ssl.CipherStrength)-bit)"
>> "=== Certificate Chain (PEM) ==="
>> # Build the chain from the remote leaf certificate
>> $remoteCert = [System.Security.Cryptography.X509Certificates.X509Certificate2]::new($ssl.RemoteCertificate)
>> $xchain = [System.Security.Cryptography.X509Certificates.X509Chain]::new()
>> $null = $xchain.Build($remoteCert)
>> $i = 0
>> foreach ($elem in $xchain.ChainElements) {
>> $i++
>> $c = $elem.Certificate
>> "----- Certificate $i -----"
>> "Subject : $($c.Subject)"
>> "Issuer : $($c.Issuer)"
>> "NotBefore: $($c.NotBefore)"
>> "NotAfter : $($c.NotAfter)"
>> ""
>> }
>> }
>> finally {
>> $ssl.Dispose()
>> $tcp.Dispose()
>> }
=== Protocol ===
Tls12
=== Cipher ===
Aes256 (256-bit)
=== Certificate Chain (PEM) ===
----- Certificate 1 -----
Subject : CN=WIN-SRVR02.networker.lan, OU=NetWorker, O=DELL, L=Round Rock, S=TX, C=US
Issuer : CN=WIN-SRVR02.networker.lan, OU=NetWorker, O=DELL, L=Round Rock, S=TX, C=US
NotBefore: 12/12/2025 15:16:03
NotAfter : 12/06/2050 15:16:03
This output shows that the TLS protocol negotiated is TLSv1.2, and that the AUTHC server is using a valid self-signed certificate.
Affected Products
NetWorker, NetWorker Management ConsoleProducts
NetWorker FamilyArticle Properties
Article Number: 000219009
Article Type: Solution
Last Modified: 16 يوليو 2026
Version: 6
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