I don't believe there is a built in report for this so I had made my own, however one thing to beware of is how you choose to have SolarWinds configured to pull backups - if only changed configs get saved or if every time the job runs you save the configs. My report assumed the later and looked for Never backed up and ones older than 25 hours (allowing a 1 day grace to notice & correct issues):
OldLastRunningConfig.ConfigMgmtReport
<Report Version="2.0" ReportType="Node Details" Schema="F:\SolarWinds Source\Source 2003\Configuration-Management\ConfigMgmtEngine8\Schemas\Node_Details.Schema" Category="Node Details" Title="Running Configs not backed up in the last 25 hours" SubTitle="" Description="Displays timestamp for when current running config was backed up or an indication that it has never been backed up" Footer="" Grouping="" FieldList="NODES.NodeCaption,NODES.AgentIP,CONFIGS.LastRunningDownloadTime" DisplayStatus="FALSE" IncludeConfigs="FALSE" IncludeUnManaged="FALSE" MergeLikeRows="FALSE" Lines="Horizontal" SQL="SELECT Nodes.*,[CONFIGS].[LastRunningDownloadTime]
from
(select Nodes.NodeID, Max (ConfigArchive.downloadtime) as LastRunningDownloadTime
from Nodes left join ConfigArchive on ConfigArchive.NodeId = Nodes.NodeId
and ConfigArchive.ConfigType='Running'
group by
Nodes.NodeID) as Configs left join Nodes on Nodes.NodeId=Configs.NodeId
WHERE ((LastRunningDownloadTime <= DATEADD(hour, -25, GETDATE())) OR (LastRunningDownloadTime is null))
ORDER BY [NODES].[NodeCaption],[NODES].[AgentIP],[CONFIGS].[LastRunningDownloadTime]" SelectClause="SELECT Nodes.*,[CONFIGS].[LastRunningDownloadTime]" FromClause="from
(select Nodes.NodeID, Max (ConfigArchive.downloadtime) as LastRunningDownloadTime
from Nodes left join ConfigArchive on ConfigArchive.NodeId = Nodes.NodeId
and ConfigArchive.ConfigType='Running'
group by
Nodes.NodeID) as Configs left join Nodes on Nodes.NodeId=Configs.NodeId" WhereClause="WHERE ((LastRunningDownloadTime <= DATEADD(hour, -25, GETDATE())) OR (LastRunningDownloadTime is null))" OrderByClause="ORDER BY [NODES].[NodeCaption],[NODES].[AgentIP],[CONFIGS].[LastRunningDownloadTime]" TopX="All" TopXCount="10" TopXPercent="10" Orientation="Landscape"><FieldSelection></FieldSelection><CriteriaSelection><QUERY><KIND>1</KIND><COMPLEX><TAG></TAG><CONNECTIVE>1</CONNECTIVE><CHECKED>1</CHECKED></COMPLEX></QUERY>
</CriteriaSelection></Report>