RHCE knowledge point

INSTALLATIONUsetherightbootdiskfortheinstallation: boot. img-Standardinstallationbootnet.img-Networkinstallationpcmcia.img-PCMCIArequiredinstallationInstallLILOinan

INSTALLATION
　　
Use the right boot disk for the installation:
　　
Boot. img-Standard installation
Bootnet. img-Network installation
Pcmcia. img-PCMCIA required installation
Install LILO in an appropriate location:
　　
MBR-If LILO will be the default bootloader
First partition of boot sector-If you're using another OS bootloader
　　
　　
LINUX FILESYSTEM
　　
The root filesystem is made up of 12 directories by default:
　　
/Bin/home/proc
/Dev/opt/usr
/Etc/lost + found/var
/Sbin/mnt/usr/local
　　
　　
KERNEL COMPILING
Three options are available for processing a kernel:
　　
Make config
Make menuconfig
Make xconfig
There are two types of kernel images:
　　
Zlmage (small kernel images)
Bzlmage (compressed kernel images)
The seven steps for compiling a kernel are:
　　
Make configuration (makeconfig, make menuconfig, or make xconfig)
Make dep
Make clean
Make bzlmage (or zlmage)
Make modules
Make modules_install
Configure LILO and reboot
Three shorter steps for compiling a kernel are:
　　
Make configuration (make config, make menuconfig, or make xconfig)
Make dep clean bzlmage modules modules_install
Configure LILO and reboot
　　
　　
X WINDOW SYSTEM
Three X configuration tools are:
　　
Xconfigurator
XF86Setup
Xf86config
　　
　　
APACHE
The main configuration directory is/etc/httpd/conf /.
　　
The main Apache configuration file is httpd. conf, used for httpd server configuration.
　　
To configure a virtual host, follow these steps:
　　
Set NameVirtualHost (NameVirtualHost 192.168.0.1 ).
Set VirtualHost ().
Set DocumentRoot.
Set ServerName.
Set ErrorLog.
Set TransferLog.
Close VirtualHost ().
Restart httpd (/etc/rc. d/init. d/httpd restart ).
　　
EMAIL
There are three components of email:
　　
MTA-Mail transfer agent (sendmail)
MDA-Mail delivery agent (procmail)
MUA-Mail user agent (Pine, Elm, Mutt, Netscape)

DNS/BIND
To configure a domain, follow these steps:
　　
Set up a zone in/etc/named. conf.
Set up a forward zone file (db.example.com ).
Set up a reverse zone file (0.168.192.in-addr. arpa ).
Restart DNS (/etc/rd. d/init. d/named restart ).
　　
　　
FTP
To configure FTP, you need these files:
　　
/Etc/ftpaccess-For ftpd configuration
/Etc/ftpusers-For user access control
/Etc/ftphost-For host access control
　　
　　
SAMBA
Files used with SMB are:
　　
/Etc/smb.com-Main configuration file
/Etc/smbpasswd-Password configuration file
To set up an SMB share, follow these steps:
　　
Add share to/etc/smb. conf.
Use testparm to test/etc/smb. conf syntax.
Restart SMB (/etc/rc. d/init. d/smb restart ).
Access SMB share (smbclient ).
　　
　　
DHCP
To configure a DHCP server, follow these steps:
　　
Check for MULTICAST (ifconfig ).
Add route 255.255.255 (route ).
Start DHCP (/etc/rd. c/init. d/dhcpd start ).
Verify DHCP service (/usr/sbin/dhcpd-d-f ).
Configure/etc/dhcpd. conf.
　　
　　
INETD
To enable or disable network services controlled by inetd, you edit the/etc/inetd. conf file.
　　
　　
　　
TCP_WRAPPERS
Controls access to only those services managed by inetd.
　　
To specify access rules, edit:
　　
/Etc/hosts. allow
/Etc/hosts. deny
　　
　　
ROUTING
To set up network and routing services, use these tools:
　　
Use route tp sipw pr cpmfogire the IP routing table.
Use netstat to display network connections, routing tables and interface information.
Use netcfg to configure network information, routing, host information, default servers, and interface connections.
Use ifconfig to configure a network interface.
　　
　　
IPCHAINS
The default chains are:
　　
Input-Controls incoming connections
Output-Controls outgoing connections
Forward-Forwards connections
　　
　　
DEBUGGING
To debug your machine, follow these steps:
　　
Boot your machine. Decide whether you can fix the machine as is, whether you need to boot the system into single-user mode, or whether you need to use system rescue disks.
Obtain a set of boot disks.
Boot the machine with a floppy disk (or boot into single-user (linux single) mode as determined by step ).
Check your filesystem. (fsck)
Mount your filesystems. (mount)
First mount your root partition. Then mount any other filesystems under your root (/) partition. (mount/dev/hda5 // mnt/harddrive)
Fix the problem.
Check to see if you need to restart LILO. (lilo, or lilo-r)
Sync any changes to the disk. (sync)
Unmount any manually mounted filesystems. (umount)
Remove any floppies, CDs, and so on, and reboot (Ctrl + Alt + Del ).