2518926 - TrexException is getting recorded without using TREX

In the NWA Logviewer, below error messages is getting recorded even TREX is not being used in the landscape

com.sapportals.trex.TrexException: This exception is thrown by failed search engine and text mining actions: Message: Invalid entry in configuration: section nameserver, key address, value tcpip://<nameserverhost>:<nameserverport> is invalid (Errorcode 7213);

To-String: com.sapportals.trex.TrexException: Invalid entry in configuration: section nameserver, key address, value tcpip://<nameserverhost>:<nameserverport> is invalid (Errorcode 7213); Trex-Msg: 7213; Trex-Code: {4} 

TrexException: Failed to list the active HttpServers: Message: Class: com.sap.aii.af.service.trex.TrexException : Invalid entry in configuration: section nameserver, key address, value tcpip://<nameserverhost>:<nameserverport> is invalid.

• SAP NetWeaver 7.3
• SAP enhancement package 1 for SAP NetWeaver 7.3
• SAP NetWeaver 7.4
• SAP Netweaver 7.5
• KMC Content Management

Enterprise Portal 7.0, EP 7.0, Enterprise Portal 7.01, EP 7.01, Enterprise Portal 7.02, EP 7.02, Enterprise Portal 7.03, EP 7.03, Enterprise Portal 7.1, EP 7.1, Enterprise Portal 7.2, EP 7.2, Enterprise Portal 7.30, EP 7.30, Enterprise Portal 7.31, EP 7.31, Enterprise Portal 7.40, EP 7.4, Enterprise Portal 7.50, EP 7.5 , KBA , BC-JAS-DPL , Deployment , EP-KM-CM , Content Management , BC-TRX , TREX , Problem