I have changed the kerb5.conf as below, but still the same error.
[logging]
default = FILE:/var/log/krb5libs.log
kdc = FILE:/var/log/krb5kdc.log
admin_server = FILE:/var/log/kadmind.log
[libdefaults]
ticket_lifetime = 24000
default_realm=qcorpaa.aa.com
default_tgs_enctypes =rc4-hmac des-cbc-md5
default_tkt_enctypes =rc4-hmac des-cbc-md5
default_keytab_name = FILE:/etc/krb5.keytab
dns_lookup_realm = false
dns_lookup_kdc = false
forwardable = true
proxiable = true
udp_preference_limit = 1
[realms]
QCORPAA.AA.COM = {
kdc = dc2.qcorpaa.aa.com:88
admin_server = dc2.qcorpaa.aa.com:764
default_domain = qcorpaa.aa.com
}
[domain_realm]
.qcorpaa.aa.com=QCORPAA.AA.COM
qcorpaa.aa.com=QCORPAA.AA.COM
[03/14/2017][01:01:48][61044][34556784][22872091-2f901773-7c7eea98-b1db956a-aa79d87e-e8][CSmCredentialManager::GatherAdvancedAuthCredentials][Calling SM_WAF_HTTP_PLUGIN->ProcessAdvancedAuthCredentials.]
[03/14/2017][01:01:48][61044][34556784][22872091-2f901773-7c7eea98-b1db956a-aa79d87e-e8][SmKcc::getCredentials][Kerberos Credential Cache login failed with service principal HTTP/scappd88.qcorpaa.aa.com@QCORPAA.AA.COM: Key table entry not found]
[03/14/2017][01:01:48][61044][34556784][22872091-2f901773-7c7eea98-b1db956a-aa79d87e-e8][CSmCredentialManager::GatherAdvancedAuthCredentials][SM_WAF_HTTP_PLUGIN->ProcessAdvancedAuthCredentials returned SmFailure.]
[03/14/2017][01:01:48][61044][34556784][22872091-2f901773-7c7eea98-b1db956a-aa79d87e-e8][ProcessAdvancedAuthentication][CredentialManager returned SmFailure, end new request.]
[03/14/2017][01:01:48][61044][34556784][][ReportHealthData][Accumulating HealthMonitorCtxt.]