202-450 Exam Dumps : LPIC-2 - Exam 202 (part 2 of 2), version 4.5

The http_port directive in squid.conf sets the port number or numbers that Squid will use to listen for client requests. You can specify multiple socket addresses with different port numbers and options. By default, Squid listens on port 3128 on all network interfaces. You can change the port number or bind the socket to a specific IP address if needed. For example, to set the port to 8080, you can write:

http_port 8080

To configure Squid to listen only on the 192.0.2.1 IP address on port 3128, you can write:

http_port 192.0.2.1:3128

References:

• Squid proxy configuration tutorial on Linux
• squid : http_port configuration directive
• Configuring the Squid Service to Listen on a Specific Port or IP Address

The option in named.conf that specifies which hosts are permitted to ask for domain name information from the server is allow-query. The allow-query option is used to define an access control list (ACL) that matches the source IP address of the DNS query. The ACL can be a list of IP addresses, networks, keywords, or predefined ACL names. The default value of allow-query is any, which means that any host can query the server. However, this can pose a security risk, as the server may be exposed to unwanted or malicious queries. Therefore, it is recommended to restrict the allow-query option to only the hosts that need to access the server, such as the local network or trusted clients. For example, the following option allows only the hosts in the 192.168.1.0/24 network and the localhost to query the server:

allow-query { 192.168.1.0/24; localhost; };

The other options are not valid in named.conf. allowed-hosts, accept-query, permit-query, and query-group are not recognized keywords by BIND.

References:

• LPIC-2 exam 202 objectives, topic 208.1, “Implementing a web server”
• BIND 9 Administrator Reference Manual, chapter 6, “Access Control Lists and TSIG”
• How to Configure DNS Server with TSIG on CentOS 8

 OpenVAS is a network security scanner project that, at the core, is a server with a set of network vulnerability tests (NVTs) to detect security problems in remote systems and applications. It is an open-source tool that was forked from Nessus, a popular commercial scanner. OpenVAS can perform comprehensive scans of networks and hosts, as well as web application scanning and compliance testing. It also provides a graphical user interface (GUI) and a command-line interface (CLI) for managing scans and reports. References:

• Greenbone Vulnerability Management - Gentoo wiki
• The Best Network Vulnerability Scanners Tested in 2023 - Comparitech