Make sure you have Firefox, Java Runtime Environment and Java plugin for Firefox. In Debian, you need these packages:
iceweasel
openjdk-7-jre
icedtea-7-plugin
DRAC 4 only supports SSLv3 and TLS 1.0 but they’re disabled in recent Firefox/Iceweasel versions – you get Secure Connection Failed error. To fix it, go to about:config and set security.tls.insecure_fallback_hosts to a comma separated list of hosts you want connect to (e.g. 10.1.2.3,10.2.3.4). You can now connect and login to DRAC 4.
DRAC 4 only supports SSL_RSA_WITH_RC4_128_MD5 and SSL_RSA_WITH_RC4_128_SHA cipher suites but they’re disabled in recent Java versions – you get an exception and Unknown Main-Class error if you try to open console. To fix it, enable SSL_RSA_WITH_RC4_128_MD5 cipher suite by setting
deployment.plugin.jvm.arguments=-Dhttps.cipherSuites=TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA,
TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA,
TLS_RSA_WITH_AES_256_CBC_SHA,
TLS_ECDH_ECDSA_WITH_AES_256_CBC_SHA,
TLS_ECDH_RSA_WITH_AES_256_CBC_SHA,
TLS_DHE_RSA_WITH_AES_256_CBC_SHA,
TLS_DHE_DSS_WITH_AES_256_CBC_SHA,
TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA,
TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA,
TLS_RSA_WITH_AES_128_CBC_SHA,
TLS_ECDH_ECDSA_WITH_AES_128_CBC_SHA,
TLS_ECDH_RSA_WITH_AES_128_CBC_SHA,
TLS_DHE_RSA_WITH_AES_128_CBC_SHA,
TLS_DHE_DSS_WITH_AES_128_CBC_SHA,
TLS_ECDHE_ECDSA_WITH_3DES_EDE_CBC_SHA,
TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA,
SSL_RSA_WITH_3DES_EDE_CBC_SHA,
TLS_ECDH_ECDSA_WITH_3DES_EDE_CBC_SHA,
TLS_ECDH_RSA_WITH_3DES_EDE_CBC_SHA,
SSL_DHE_RSA_WITH_3DES_EDE_CBC_SHA,
SSL_DHE_DSS_WITH_3DES_EDE_CBC_SHA,
TLS_EMPTY_RENEGOTIATION_INFO_SCSV,
SSL_RSA_WITH_RC4_128_MD5
in ~/.icedtea/deployment.properties (Debian Wheezy) or ~/.config/icedtea-web/deployment.properties (Debian Jessie). Make sure everything is on single line and there are no spaces around the commas. You can also set it using itweb-settings (JVM Settings->Set JVM arguments for plugin) but there’s a bug – a backslash is prepended before equal (=) sign in deployment.properties so you have to edit the file then.
Console will not open from the DRAC web interface, you have to enter URL manually (e.g. https://10.1.2.3/cgi/vkvm). You may want to bookmark it.