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1. All services in Red Hat can use TCP Wrappers. True or False? 1a. False. A service needs to have support for TCP Wrappers to be able to use it. 2. The firewall service is disabled by default. True or False? 2a. False. The firewall service...
1. What is the point of using SELinux? 1a. SELinux provides enhanced granular security for the Linux operating system. 2. What are SELinux Booleans? 2a. SELinux Booleans provide restrictions to different aspects of a service. 3. What command can you use to change the context of...
1. What two commands are used for package management? 1a. The yum and rpm commands are used for package management. 2. What are the three modes in which the rpm command can operate? 2a. The rpm command can operate in install, query, or verify modes. 3....
1. What command displays your current interfaces and IP address? 1a. ifconfig 2. What does ifconfig 172.168.1.100 netmask 255.255.255.0 eth1 do? 2a. This command sets the eth1 interface to have a static IP address of 172.168.1.100 with a netmask of 255.255.255.0. 3. What command can you...
1. What is the difference between an ext2 and ext3 file system? 1A. An ext3 file system has journaling built in to it, whereas the ext2 file system doesn’t. 2. What command can you use to create a file system? 2a. mkfs.ext4 3. Can you grow...
1. GRUB has three stages. Can you name them? Ans: Stage 1: During this stage, the primary bootloader is read into memory by the BIOS from the MBR. Stage 1.5: During this stage, the bootloader is read into memory by the stage 1 bootloader (only if necessary). Stage...
1. Red Hat Enterprise Linux 5 supports LUKS encryption. True or False? 1A. False. Red Hat Enterprise Linux 6 is the only version that officially supports LUKS encryption. 2. In Red Hat Enterprise Linux 6, SELinux is set to Enforcing by default during the installation. True or...
When you want to troubleshoot the NTP service, there are a few commands that can help you out. First, if you want to update the time manually, you can use the ntpdate command.
Like the DHCP server, NTP requires only firewall rules to operate (no SELinux configuration is necessary).
Before any of the clients can start obtaining an IP address from the DHCP server, you need to deal with the security requirements for the DHCP server. They include adding a firewall rule with iptables and disabling any SELinux options that prevent the DHCP service from...