Linux 18th Day Self-study network management

Linux 18th Day Self-study network management

Time: 20180804

Directory

Ifconfig

Ip

GUI Configuration Network

Configuration file Modify NIC parameters

Routing Management IP, route

Common network detection Tools ping, traceroute, SS, Netstat, Iftop, MTR, nethogs

Linux Network Management

Ifconfig Viewing network interface configuration

Package name Net-tools

Enable or disable a network interface

Ifconfig IFNAME Up|down

Ifup IFNAME

Ifdown IFNAME

Set IP address (cent6 effective, 7 not possible)

Ifconfig IFNAME Ip/netmask [up]

Ifconfig IFNAME IP netmask netmask

The address you set will take effect immediately, but will not be permanently enforced.

IP configuration NIC Parameters

Package name Iproute

IP [OPTIONS] OBJECT {COMMAND | help}

OBJECT: = {link | address | addrlabel | route | rule | neigh |

ntable | Tunnel | Tuntap | maddress | Mroute | Mrule |

Monitor | xfrm | Netns | L2TP | Tcp_metrics | Token |

MACSEC}

Link

Set set interface properties

IP Link Set DEVICE

{Up|down} enable disable device

Promisc {On|off} supports promiscuous mode

Name NEWNAME set the interface with the new name

Show display interface Status

Setting parameters will take effect immediately but will not be permanent

Addr (cent7 Effective)

Add address

Del Delete address

IP addr {add|del} ifaddr dev IFNAME

Show display NIC all information

Flush Clear Protocol Address

IP addr flush [Dev IFNAME]

Route

List|show Show routes

Add route

IP route add DESTINATION via GATEWAY [Dev IFNAME]

IP route add default via 172.16.48.1

del Delete route

IP Route del DESTINATION

IP route del default

IP Route del 172.16.0.0/16

GUI Configuration Network

Cent6:setup

Package name Setuptool

Cent7:nmtui (Text User Interface for controlling NetworkManager)

Package name NetworkManager

Configuration file Modify NIC parameters

/etc/sysconfig/network-scripts/ifcfg-ifname

Modifying this profile does not take effect immediately, but is permanent.

Common parameter Descriptions

Device to which this profile is associated, which is typically the ifname in Ifcfg-ifname

Bootproto the protocol static, DHCP, NONE,BOOTP used when starting the device

HWADDR the MAC address of the NIC

nm_controlled nm is a shorthand for networkmanager and is recommended to set to No

Onboot On|off Whether this device is activated with OS boot

Type device types, Ethernet Bridge

Unique identifier of the UUID online device

IPADDR IP address of this interface

NETMASK Subnet Mask

Gateway Default Gateways

DNS1,DNS2,DNS3 DNS server address

Ipv6init Initializing IPv6 protocol address

Userctl whether to allow normal users to manage this interface

Peerdns when the value of Bootproto is DHCP, allows the DHCP server to provide a DNS server that points to

Override locally manually configured DNS servers to point to

Routing Management

Route view and Configure routing

The package name that provides this command net-tools

Add Routing route add [-net|-host] TARGET [netmask netmask] Dev IFNAME

Route add-net 192.56.76.0 netmask 255.255.255.0 Dev eth0

Route add-net 192.168.3.0 netmask 255.255.255.0 GW 172.16.0.1

Remove routing route del {-net|-host} TARGET

Route Del-net 192.168.3.0/24

This method of configuring routing takes effect only immediately, but does not take effect permanently

Configure Routing (permanent)

/etc/sysconfig/network-scripts/route-ifname

Defining formats

DESTINATION via GATEWAY [Dev IFNAME]

192.168.0.0/24 via 172.16.0.1

10.10.10.0/24 via 172.16.0.1 Dev ens33

10.1.1.0/24 via 172.16.0.1 Dev ens33

Configure host Name

echo "HOSTNAME" >/proc/sys/kernel/hostname

hostname hostname

Directly behind the host name can be directly modified, temporary effect

Permanent effective Modification method

/etc/sysconfig/network or/etc/hostname

Modify its configuration hostname permanent effect

Network Common Tools

Ping detects if the destination IP is up to

-C means sending several ping packets

-W Specifies the timeout length, in seconds

Traceroute IP

Detects gateway devices that reach the middle of the target host

MTR HOST

Network diagnostic tool incorporating ping and traceroute command functions

Netstat Network status Detection Tool

-R Display Routing table

-N Numeric digital display, do not reverse IP address to host name

-T TCP protocol-related connections

-u UDP protocol related connections

-L Listen shows a link that is in the listening state (that is, waiting for another process to connect)

-A Show All links

-P Displays the name and PID of the process associated to the associated connection

Common combinations:-rn,-TNL,-UNL,-TUNL,-tan,-TNLP

Ss

-N Numeric digital display, do not reverse IP address to host name

-T TCP protocol-related connections

-u UDP protocol related connections

-L Listen shows a link that is in the listening state (that is, waiting for another process to connect)

-A Show All links

-E Display Extended information

-m display socket memory usage information

-O State {established|fin_wait_1|fin_wait_2|listening}

Common combinations-tnl,-UNL,-tan,-TUNL,-TNLP

Iftop bandwidth consumption with connection-centric display

Nethogs Show bandwidth usage as a process-centric

Linux 18th Day Self-study network management