Correct serial number for ds certs.

ipa-server/ipaserver/dsinstance.py

@@ -262,7 +262,7 @@ class DsInstance(service.Service):
         ca = certs.CertDB(dirname)
         if self.pkcs12_info:
             ca.create_from_pkcs12(self.pkcs12_info[0], self.pkcs12_info[1])
-            ca.cur_serial = 2000
+            ca.cur_serial = 2100
         else:
             ca.create_self_signed()
         ca.create_server_cert("Server-Cert", "cn=%s,ou=Fedora Directory Server" % self.host_name)