I am currently working with our Okta team to get SSO working with Splunk. However, we cannot get the assertionconsumerservice URL to send. We've tried adding the field manually in authentications.conf and the field still doesn't send.
Here's the authentication.conf with some things removed.
[authentication]
authSettings = saml
authType = SAML
[roleMap_SAML]
admin =
[userToRoleMap_SAML]
[saml]
entityId = splunk-
fqdn = https://10.97.193.128:8000
idpCertPath = idpCert.pem
idpSSOUrl = https://(removed).okta.com/appgroup_splunkawsdev_1/exkl1nyhftY6VWwy40x7/sso/saml
issuerId = http://www.okta.com/exkl1nyhftY6VWwy40x7
redirectAfterLogoutToUrl = http://www.splunk.com
redirectPort = 0
AssertionConsumerServiceURL = https://10.97.193.128:8000/saml/acs
replicateCertificates = true
signAuthnRequest = false
signatureAlgorithm = RSA-SHA1
signedAssertion = true
sloBinding = HTTPPost
sslKeysfile = /opt/splunk/etc/auth/server.pem
sslKeysfilePassword =
ssoBinding = HTTPPost
remove that AssertionConsumeServerURL
create an okta local group on okta and map it to your admin user, and put it on the config there
[roleMap_SAML]
admin = OktaGroupCreatedinOkta
test iDP initated login to splunk? if that works then SP initiated login should work now as well.
post your authentication.conf on the search head