Question | Answer |
RPM: Query Options? | -qa = all installed packages, -qd = documents,-qd = documentation files, -ql = list files in a package |
Yum commands: | list, install, update, remove |
Mount Options: | -a = mount what should be mounted automatically (in fstab), -t = filesystem type |
fstab fields in order: | source, destination, type, options, backup?(yes/no), verify?(yes/no) |
Location of interface config files: | /etc/ sysconfig / network-scripts / ifcfg-eth* |
Udev? | Dynamic device configuration system |
Location of resolver config? | /etc/resolv.conf |
Location of general networking config? | /etc/sysconfig/network |
What should be inside of resolv.conf? | nameserver 172.16.30.** , might have a search line (optional) |
What should be inside of network config? | NETWORKING=yes; HOSTNAME=abcd1234 |
What should be inside of interface config? | DEVICE, BOOTPROTO, ONBOOT, HWADDR, IPADDR, NETMASK, TYPE, GATEWAY |
How to list interfaces detected by the kernel? | lspci |
How to verify naming of interfaces by device manager? | dmesg | grep -i eth |
Command to list your hostname? | hostname |
What is the purpose of the search line in the resolv.conf? | FQDN completion when no domain suffix is supplied as part of the query. |
What command to use to check your default gateway? | route |
What is inside the /etc/hosts file? | 127.0.0.1 localhost localhost.localdomain; you can put in other addresses for name resolution as well. |
What is /etc/nsswitch.conf? | Do we use hosts and/or resolv.conf and in which order to check? |
Command used to check network services? | netstat -tupan |
When a client connects to a server, which port does it use? | Server port will likely be well-known (0-1023), client port will be dynamic (49152-65535) |
Where does xinetd look up the port numbers for a service? | /etc/services (preferred) or the service config file /etc/xinetd.d/ |
What happens if xinetd has a conflict with a port number (different in 2 places)? | The service is generally crippled. |
TCP Wrapper? | /etc/hosts.allow or hosts.deny, defines specific hosts allowed or denied. |
How do you set a service running on xinetd to use a specific interface? | Use the bind or interface directives |
Can you use telnet to log in as root? | Not unless you edit /etc/securetty |
Layout of telnet command? | telnet <host ip> <port#> |
SSH server config file? | /etc/ssh/sshd_config |
SSH authentication methods? | User, User with public key, Host, Host with public key. |
Where do users go when logging in with ftp? | Existing account = home directory, Anon = /var/ftp , in chroot jail. FTP can rarely also have it's own users set up. |
How to get help in ftp? | At ftp prompt: ? , help , help <command> |
Which ftp server did we use in class? | vsftpd |
Where does ftp transfer activity get logged by default? | /var/log/xferlog |
FTP run in standalone or with xinetd? | Both xinetd and standalone are valid options. |
Vsftpd option for stand alone mode? | listen = yes |
Vsftpd option for anonymous mode? | anonymous_enable = yes (default = yes) |
Vsftpd option to allow local users to log in? | local_enable = yes (default = yes) |
Vsftpd option to allow anon users to upload? | anon_upload_enable = yes (default = no) |
Vsftpd option to allow deletion of files? | write_enable = yes (default = yes) |
IP Aliasing? | Binding a second IP to the same interface. |
Rsync config file location? | /etc/rsyncd.conf (after you make it, lol) |
Rsync module options: | write only, read only, path, auth users, secrets file |
Rsync secrets file config? | user:password , have to chmod it to 600 permission. |
Rsync command usage: downloading | rsync [user@]host::module/file file |
Rsync command usage: uploading | rsync file [user@]host::module[/file] |
Package name of the DNS server software | bind |
How to do a reverse lookup with dig command? | dig -x 8.8.8.8 |
How to look up name server with dig command? | dig www.google.com NS |
How to look up name server with nslookup command? | nslookup -type=NS www.google.com |
How to do a lookup using a specific name server using dig command? | dig @8.8.8.8 www.microsoft.com |
Config file for bind? | /etc/named.conf |
What type of zone for root domain servers? | type = hint |
Where do log messages go for bind? | /var/log/messages and/or log file specified in bind config (named.conf) |
How to restart bind server? | service named restart |
Bind global options block statement called? | options |
If a recursive name server cannot answer query from it's own records, where does it go next? | Root name servers. |
How to get separate config files to be used by named.conf? | Include statements |
Do all resolvers use the search line in resolv.conf? | nslookup = yes, dig = NOPE! |
Which line in interface config can cause problems for resolv.conf? | PEERDNS, if set to YES could overwrite the resolv.con, should be set PEERDNS=no |
Why configure a localhost zones? | Prevents queries of localhost from reaching the root servers. |
Bind: option to configure interfaces to use? | listen-on |
Bind: option to configure who is allowed to use name server? | allow-query |
Bind: option to configure who can do recursive queries? | allow-recursion |
Commands to check named.conf syntax? | named-checkconf and named-checkzone |
Bind: setting up forwarders? | In named.conf options block statement add: forwarders { 8.8.8.8; }; |
How to trace name resolution path? | dig www.google.com +trace |
Minimum BIND TTL value? | 300, anything less than 300 is irrational and will be changed to 300. |