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===  Enterprise 7 Note
+
===  Enterprise 7 Note ===
 
Networking drastically changed under Enterprise 7, which now has Network Manager fully integrated (which was recommended to be uninstalled in previous releases when used on a server/static configuration). On 7, the convention is now not to modify any config files (which may be auto-generated, and/or will get overwritten by updates), but to use command-line utilities to modify any of the configuration settings/parameters (which normally does not modify the primary config file, but creates an override config file usually in a separate location).
 
Networking drastically changed under Enterprise 7, which now has Network Manager fully integrated (which was recommended to be uninstalled in previous releases when used on a server/static configuration). On 7, the convention is now not to modify any config files (which may be auto-generated, and/or will get overwritten by updates), but to use command-line utilities to modify any of the configuration settings/parameters (which normally does not modify the primary config file, but creates an override config file usually in a separate location).
  
===  Network Setup (ent 7)
+
===  Network Setup (ent 7) ===
1. determine interface and connection name setup, for the subsequent nmcli commands, use what it shows for the Connection name (Device and Connection name are normally the same, but not always the same, this needs to be checked to verify what to use).
+
1. determine interface and connection name setup for the subsequent nmcli commands, use what it shows for the Connection name (Device and Connection name are normally the same, but not always the same - this needs to be checked to verify what to use).<br>
 +
Note: "show" is a default argument in most cases, and does not need to be specified, unless other "show" arguments/details are needed (as in: nmcli dev show eno16777728)
 
  # nmcli dev
 
  # nmcli dev
  
 
2. configure the interface, IP, and gateway (defaults to "automatic" (DHCP), change to "manual" to be able to configure static parameters - settings saved in an ifcfg-interface file in /etc/sysconfig/network-scripts/, in this example; ifcfg-eno16777728)
 
2. configure the interface, IP, and gateway (defaults to "automatic" (DHCP), change to "manual" to be able to configure static parameters - settings saved in an ifcfg-interface file in /etc/sysconfig/network-scripts/, in this example; ifcfg-eno16777728)
Note: the network device can be determined by doing a "nmcli dev" (show/list devices, "show" is a default argument in most cases, and does not need to be specified, unless other "show" arguments/details are needed)
 
 
  # nmcli con mod eno16777728 ipv4.method manual ipv4.addresses 172.100.200.140/24 ipv4.gateway 172.100.200.1
 
  # nmcli con mod eno16777728 ipv4.method manual ipv4.addresses 172.100.200.140/24 ipv4.gateway 172.100.200.1
  
3. configure hostname (saved in /etc/hostname) and domain (saved in an ifcfg-interface file in /etc/sysconfig/network-scripts/)
+
3. configure hostname (saved in /etc/hostname) and domain (saved in an ifcfg-interface file in /etc/sysconfig/network-scripts/ and in /etc/resolv.conf)
 
  # nmcli gen hostname ks-c7a.lab.example.com
 
  # nmcli gen hostname ks-c7a.lab.example.com
 
  # nmcli con mod eno16777728 ipv4.dns-search lab.example.com
 
  # nmcli con mod eno16777728 ipv4.dns-search lab.example.com
  
4. configure DNS servers (see Data Center Services page for the DNS servers to use for each data center - saved in an ifcfg-interface file in /etc/sysconfig/network-scripts/)
+
4. configure DNS servers ((use DNS servers appropriate for your internet provider, for your own internal network, or for your local data center - saved in an ifcfg-interface file in /etc/sysconfig/network-scripts/ and in /etc/resolv.conf)
 
  # nmcli con mod eno16777728 ipv4.dns 172.100.170.90,172.100.130.90
 
  # nmcli con mod eno16777728 ipv4.dns 172.100.170.90,172.100.130.90
  
Line 20: Line 20:
 
  # nmcli con show eno16777728
 
  # nmcli con show eno16777728
  
 
+
===  Network Setup (before ent 7) ===
===  Network Setup (before ent 7)
+
 
most of this is common knowledge, but some of these additional steps have been added (moreso) as a comparison to the new ent 7 listing/steps (above)
 
most of this is common knowledge, but some of these additional steps have been added (moreso) as a comparison to the new ent 7 listing/steps (above)
  
Line 31: Line 30:
 
  NETMASK=255.255.255.0
 
  NETMASK=255.255.255.0
  
1b. configure the default gateway and disable the dynamic link-local (DHCP network) address in /etc/sysconfig/network
+
1b. configure the default gateway and disable the dynamic link-local (DHCP network) address in /etc/sysconfig/network<br>
 
Note: ent 6 defaults to/prefers quotes around the params, i.e. GATEWAY="172.100.130.1"
 
Note: ent 6 defaults to/prefers quotes around the params, i.e. GATEWAY="172.100.130.1"
 
  GATEWAY=172.100.130.1
 
  GATEWAY=172.100.130.1
Line 44: Line 43:
  
 
2c. set the IP and hostname info in /etc/hosts (required for 'hostname -s' and other types of resolution)
 
2c. set the IP and hostname info in /etc/hosts (required for 'hostname -s' and other types of resolution)
  172.100.200.140  ks-c7a ks-c7a.lab.example.com
+
  172.100.200.140  ks-c7a.lab.example.com ks-c7a
  
3. configure the DNS servers in /etc/resolv.conf (see Data Center Services page for the DNS servers to use for each data center)
+
3. configure the DNS servers in /etc/resolv.conf (use DNS servers appropriate for your internet provider, for your own internal network, or for your local data center)
 
  nameserver 172.100.170.90
 
  nameserver 172.100.170.90
 
  nameserver 172.100.130.90
 
  nameserver 172.100.130.90
Line 56: Line 55:
 
  # ip addr
 
  # ip addr
  
 
+
===  Changing the IP (ent 7) ===
===  Changing the IP (ent 7)
+
1. set the new IP and netmask<br>
1. set the new IP and netmask
+
 
Note: if the IP is not getting set, please check or go through the Network Setup steps (above), specifically see the note on the default setting with DHCP/manual mode
 
Note: if the IP is not getting set, please check or go through the Network Setup steps (above), specifically see the note on the default setting with DHCP/manual mode
 
  # nmcli con mod eno16777728 ipv4.addresses 172.100.200.140/24 ipv4.gateway 172.100.200.1
 
  # nmcli con mod eno16777728 ipv4.addresses 172.100.200.140/24 ipv4.gateway 172.100.200.1
Line 65: Line 63:
 
  # nmcli con mod eno16777728 ipv4.gateway 172.100.200.1
 
  # nmcli con mod eno16777728 ipv4.gateway 172.100.200.1
  
2. restart networking
+
2. restart networking<br>
 
Note: this has worked remotely over ssh, as long as the two commands are entered together as per this example, otherwise doing the single down command will cause you to lose your connection and require console access to resolve/fix
 
Note: this has worked remotely over ssh, as long as the two commands are entered together as per this example, otherwise doing the single down command will cause you to lose your connection and require console access to resolve/fix
 
  # nmcli con down eno16777728 ; nmcli con up eno16777728
 
  # nmcli con down eno16777728 ; nmcli con up eno16777728
  
 
+
===  Changing the IP (before ent 7) ===
===  Changing the IP (before ent 7)
+
1. set the new IP and netmask in the ifcfg-interface file (usually ifcfg-eth0) under /etc/sysconfig/network-scripts/<br>
1. set the new IP and netmask in the ifcfg-interface file (usually ifcfg-eth0) under /etc/sysconfig/network-scripts/
+
 
Note: ent 6 defaults to/prefers quotes around the params, i.e. NETMASK="255.255.255.0", ent 6 also introduced CIDR notation, ex; PREFIX="24" to replace the old/longer netmask convention (NETMASK="255.255.255.0")
 
Note: ent 6 defaults to/prefers quotes around the params, i.e. NETMASK="255.255.255.0", ent 6 also introduced CIDR notation, ex; PREFIX="24" to replace the old/longer netmask convention (NETMASK="255.255.255.0")
 
  IPADDR=172.200.110.140
 
  IPADDR=172.200.110.140
 
  NETMASK=255.255.255.0
 
  NETMASK=255.255.255.0
  
2. set the new default gateway in /etc/sysconfig/network
+
2. set the new default gateway in /etc/sysconfig/network<br>
 
Note: ent 6 defaults to/prefers quotes around the params, i.e. GATEWAY="172.100.130.1"
 
Note: ent 6 defaults to/prefers quotes around the params, i.e. GATEWAY="172.100.130.1"
 
  GATEWAY=172.100.130.1
 
  GATEWAY=172.100.130.1
Line 83: Line 80:
 
  172.100.200.140  ks-c7a.lab.example.com ks-c7a
 
  172.100.200.140  ks-c7a.lab.example.com ks-c7a
  
4. restart networking
+
4. restart networking<br>
 
Note: recommended to use "&" when connected remotely so the command will continue after the network gets disconnected (your session is normally not lost in this case, and you would normally stay connected)
 
Note: recommended to use "&" when connected remotely so the command will continue after the network gets disconnected (your session is normally not lost in this case, and you would normally stay connected)
 
  # service network restart &
 
  # service network restart &
  
 
+
===  Adding Additional IP's/Aliases (ent 7) ===
===  Adding Additional IP's/Aliases (ent 7)
+
 
1. add the additional IP
 
1. add the additional IP
 
  # nmcli con mod eno16777728 +ipv4.addresses 172.100.200.140/24
 
  # nmcli con mod eno16777728 +ipv4.addresses 172.100.200.140/24
  
2. restart networking
+
2. restart networking<br>
Note: this has worked remotely over ssh, and long as the two commands are entered together as per this example, otherwise doing the single down command will cause you to lose your connection and require console access to resolve/fix
+
Note: this has worked remotely over ssh, as long as the two commands are entered together as per this example, otherwise doing the single down command will cause you to lose your connection and require console access to resolve/fix
 
  # nmcli con down eno16777728 ; nmcli con up eno16777728
 
  # nmcli con down eno16777728 ; nmcli con up eno16777728
  
 
+
===  Adding Additional IP's/Aliases (before ent 7) ===
===  Adding Additional IP's/Aliases (before ent 7)
+
 
1. create an ifcfg-interface:aliasnumber file in /etc/sysconfig/network-scripts/ (ifcfg-eth0:0 for this example), with the following contents
 
1. create an ifcfg-interface:aliasnumber file in /etc/sysconfig/network-scripts/ (ifcfg-eth0:0 for this example), with the following contents
 
  DEVICE="eth0:0"
 
  DEVICE="eth0:0"
Line 104: Line 99:
 
  ONPARENT="yes"
 
  ONPARENT="yes"
  
2. restart networking
+
2. restart networking<br>
 
Note: recommended to use & when connected remotely so the command will continue after the network gets disconnected (your session is normally not lost in this case, and you would normally stay connected)
 
Note: recommended to use & when connected remotely so the command will continue after the network gets disconnected (your session is normally not lost in this case, and you would normally stay connected)
 
  # service network restart &
 
  # service network restart &
  
 
+
===  Adding Static Routes (ent 7) ===
===  Adding Static Routes (ent 7)
+
Set the address range and gateway address (saved in a route-interface file in /etc/sysconfig/network-scripts/, in this example; route-eno16777728)
Set the address range and gateway address (saved in an route-interface file in /etc/sysconfig/network-scripts/, in this example; route-eno16777728)
+
 
  # nmcli con mod eno16777728 ipv4.routes "172.200.210.0/24 172.200.210.120"
 
  # nmcli con mod eno16777728 ipv4.routes "172.200.210.0/24 172.200.210.120"
  
 
+
===  Adding Static Routes (before ent 7) ===
===  Adding Static Routes (before ent 7)
+
 
Create a route-interface file (for IPv4), example /etc/sysconfig/network-scripts/route-eth0 (or route-bond0 for a bonding interface);
 
Create a route-interface file (for IPv4), example /etc/sysconfig/network-scripts/route-eth0 (or route-bond0 for a bonding interface);
 
  ADDRESS0=172.200.210.0
 
  ADDRESS0=172.200.210.0
Line 120: Line 113:
 
  GATEWAY0=172.200.210.120
 
  GATEWAY0=172.200.210.120
  
 
+
===  Quick Reference ===
===  Multi-NIC Routing (ent 7)
+
The multi-NIC routing scenario has not yet been tried/tested on Enterprise 7. Things may work correctly based on (possibly) proper gateway settings per NIC (if this works correctly under ent 7). If not, we know how to add static routes on ent 7, and can replicate the configuration for pre-ent 7 envs via Network Manager (nmcli).
+
 
+
There was some testing done here, we ended up doing the source based routing.
+
 
+
 
+
=== Multi-NIC Routing (before ent 7)
+
Before Enterprise 7, since we could not have a gateway (that works) per interface (even though it lets you set a gateway in every interface config file: which it uses to overwrite the default gateway), we have to set the default gateway to the outside or customer facing network (since we cannot possibly know all IP's/networks these connections would be coming from), and then set static routes to every possible network and host it needs access to for our inside network. These are examples for /etc/sysconfig/network-scripts/route-eth1 (where the eth0/default is the primary/outside/customer network, and eth1 in the secondary/internal/private network).
+
 
+
Static list for TEL (example, the TEL data center no longer exists)
+
# default network (set this for your specific env/stack)
+
ADDRESS0=172.200.200.0
+
NETMASK0=255.255.255.0
+
GATEWAY0=172.200.200.1
+
# VPN network
+
ADDRESS1=10.100.100.0
+
NETMASK1=255.255.255.0
+
GATEWAY1=172.200.200.1
+
# DNS host 1
+
ADDRESS2=210.210.90.80
+
NETMASK2=255.255.255.255
+
GATEWAY2=172.200.200.1
+
# DNS host 2
+
ADDRESS3=210.210.120.140
+
NETMASK3=255.255.255.255
+
GATEWAY3=172.200.200.1
+
# spacewalk host
+
ADDRESS4=172.200.90.60
+
NETMASK4=255.255.255.255
+
GATEWAY4=172.200.200.1
+
# trusted host
+
ADDRESS5=172.200.90.50
+
NETMASK5=255.255.255.255
+
GATEWAY5=172.200.200.1
+
 
+
 
+
===  Teaming (ent 7)
+
1. add the teaming inferface
+
# nmcli con add type team con-name team0 ifname team0 config '{"runner": {"name": "loadbalance"}}'
+
 
+
2. set IP address info
+
# nmcli con mod team0 ipv4.method manual ipv4.addresses 172.100.200.140/24
+
 
+
3. add the first NIC
+
# nmcli con add type team-slave con-name team0-slave1 ifname em1 master team0
+
 
+
4. add the second NIC
+
# nmcli con add type team-slave con-name team0-slave2 ifname em2 master team0
+
 
+
 
+
===  Bonding (before ent 7)
+
Before Enterprise 7, interface Bonding was configured via various config files in /etc/sysconfig/network-scripts/ (this has been rewritten in ent 7 and is now called Teaming), example setup;
+
 
+
eth0 config (ifcfg-eth0)
+
# Broadcom Corporation NetXtreme II BCM5709 Gigabit Ethernet
+
DEVICE=eth0
+
BOOTPROTO=none
+
ONBOOT=yes
+
HWADDR=D4:BE:D9:AA:D7:16
+
MASTER=bond0
+
SLAVE=yes
+
 
+
eth1 config (ifcfg-eth1)
+
# Broadcom Corporation NetXtreme II BCM5709 Gigabit Ethernet
+
DEVICE=eth1
+
BOOTPROTO=none
+
ONBOOT=yes                                                                               
+
HWADDR=D4:BE:D9:AA:D7:18
+
MASTER=bond0
+
SLAVE=yes
+
 
+
bond0 config (ifcfg-bond0)
+
DEVICE=bond0
+
BOOTPROTO=none
+
ONBOOT=yes
+
BONDING_OPTS="miimon=100 mode=1"
+
IPADDR=172.200.110.140
+
NETMASK=255.255.255.0
+
 
+
Additional bond IP's
+
bond0:0 config (ifcfg-bond0:0)
+
DEVICE=bond0:0
+
BOOTPROTO=none
+
ONBOOT=yes
+
IPADDR=172.200.110.200
+
NETMASK=255.255.255.0
+
 
+
ifconfig output
+
bond0    Link encap:Ethernet  HWaddr D4:BE:D9:AA:D7:16
+
          inet addr:172.200.110.140  Bcast:172.200.110.255  Mask:255.255.255.0
+
          inet6 addr: fe80::d6be:d9ff:feaa:d716/64 Scope:Link
+
          UP BROADCAST RUNNING MASTER MULTICAST  MTU:1500  Metric:1
+
          RX packets:951518061 errors:0 dropped:244110 overruns:0 frame:0
+
          TX packets:377721364 errors:0 dropped:0 overruns:0 carrier:0
+
          collisions:0 txqueuelen:0
+
          RX bytes:868579848472 (808.9 GiB)  TX bytes:88332253777 (82.2 GiB)
+
+
bond0:0  Link encap:Ethernet  HWaddr D4:BE:D9:AA:D7:16
+
          inet addr:172.200.110.200  Bcast:172.200.110.255  Mask:255.255.255.0
+
          UP BROADCAST RUNNING MASTER MULTICAST  MTU:1500  Metric:1
+
+
eth0    Link encap:Ethernet  HWaddr D4:BE:D9:AA:D7:16
+
          UP BROADCAST RUNNING SLAVE MULTICAST  MTU:1500  Metric:1
+
          RX packets:244110 errors:0 dropped:244110 overruns:0 frame:0
+
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
+
          collisions:0 txqueuelen:1000
+
          RX bytes:15623040 (14.8 MiB)  TX bytes:0 (0.0 b)
+
+
eth1    Link encap:Ethernet  HWaddr D4:BE:D9:AA:D7:18
+
          UP BROADCAST RUNNING SLAVE MULTICAST  MTU:1500  Metric:1
+
          RX packets:3095102322 errors:0 dropped:0 overruns:0 frame:0
+
          TX packets:2613440853 errors:0 dropped:0 overruns:0 carrier:0
+
          collisions:0 txqueuelen:1000
+
          RX bytes:2651544232860 (2.4 TiB)  TX bytes:1948544659918 (1.7 TiB)
+
 
+
 
+
===  Renumbering Ports (ent 6)
+
Example is from a R630 system used as an appliance with 4 ports on the motherboard that had 2 coppper & 2 fiber. For this appliance they wanted the 2 copper ports to be eth0/1 and the fiber be eth2/3, but a recently built system had them designated in reverse. The renaming/mapping went as follows;
+
eth0 (fiber)  -> eth2
+
eth1 (fiber)  -> eth3
+
eth2 (copper) -> eth0
+
eth3 (copper) -> eth1
+
 
+
Relabel the ports by changing the udev net rules file, change eth0 to eth2, etc, change only the NAME= lines (as mentioned in the comment at the top of the file)
+
# vi /etc/udev/rules.d/70-persistent-net.rules
+
 
+
Rename all the network config files
+
# cd /etc/sysconfig/network-script/
+
# cp ifcfg-eth* /tmp/
+
# cp /tmp/ifcfg-eth0 ifcfg-eth2
+
etc
+
 
+
Fix the device names in each file, new ifcfg-eth0 has DEVICE=eth2, change this to say eth0, etc
+
# vi ifcfg-eth?
+
 
+
Reboot when done to properly pick up all the udev/network config changes/etc
+
 
+
 
+
===  Quick Reference
+
 
past what is shown above, here are a few additional/helpful commands
 
past what is shown above, here are a few additional/helpful commands
  
Line 271: Line 125:
 
  # cat /etc/sysconfig/network /etc/sysconfig/network-scripts/ifcfg-e*
 
  # cat /etc/sysconfig/network /etc/sysconfig/network-scripts/ifcfg-e*
  
Show IP Configuration (ent 7)
+
Show IP Configuration (ent 7)<br>
 
Note: run 'nmcli dev' to find the device name
 
Note: run 'nmcli dev' to find the device name
 
  # nmcli dev
 
  # nmcli dev
Line 279: Line 133:
 
  # nmcli con show ens32
 
  # nmcli con show ens32
  
Show Listening Ports (only)
+
Show Listening Ports (only)<br>
 
Note: the : in the output normally denotes a listening port
 
Note: the : in the output normally denotes a listening port
 
  # lsof -nP | grep ":"
 
  # lsof -nP | grep ":"

Latest revision as of 12:37, 9 May 2017

Enterprise 7 Note

Networking drastically changed under Enterprise 7, which now has Network Manager fully integrated (which was recommended to be uninstalled in previous releases when used on a server/static configuration). On 7, the convention is now not to modify any config files (which may be auto-generated, and/or will get overwritten by updates), but to use command-line utilities to modify any of the configuration settings/parameters (which normally does not modify the primary config file, but creates an override config file usually in a separate location).

Network Setup (ent 7)

1. determine interface and connection name setup for the subsequent nmcli commands, use what it shows for the Connection name (Device and Connection name are normally the same, but not always the same - this needs to be checked to verify what to use).
Note: "show" is a default argument in most cases, and does not need to be specified, unless other "show" arguments/details are needed (as in: nmcli dev show eno16777728)

# nmcli dev

2. configure the interface, IP, and gateway (defaults to "automatic" (DHCP), change to "manual" to be able to configure static parameters - settings saved in an ifcfg-interface file in /etc/sysconfig/network-scripts/, in this example; ifcfg-eno16777728)

# nmcli con mod eno16777728 ipv4.method manual ipv4.addresses 172.100.200.140/24 ipv4.gateway 172.100.200.1

3. configure hostname (saved in /etc/hostname) and domain (saved in an ifcfg-interface file in /etc/sysconfig/network-scripts/ and in /etc/resolv.conf)

# nmcli gen hostname ks-c7a.lab.example.com
# nmcli con mod eno16777728 ipv4.dns-search lab.example.com

4. configure DNS servers ((use DNS servers appropriate for your internet provider, for your own internal network, or for your local data center - saved in an ifcfg-interface file in /etc/sysconfig/network-scripts/ and in /etc/resolv.conf)

# nmcli con mod eno16777728 ipv4.dns 172.100.170.90,172.100.130.90

5. optional, list networking/connection info

# nmcli con show eno16777728

Network Setup (before ent 7)

most of this is common knowledge, but some of these additional steps have been added (moreso) as a comparison to the new ent 7 listing/steps (above)

1. configure the IP and gateway 1a. set the following in an ifcfg-interface file (usually ifcfg-eth0) under /etc/sysconfig/network-scripts/ Note: ent 6 defaults to/prefers quotes around the params, i.e. BOOTPROTO="none", ent 6 also introduced CIDR notation, ex; PREFIX="24" to replace the old/longer netmask convention (NETMASK="255.255.255.0")

BOOTPROTO=none
IPADDR=172.200.110.140
NETMASK=255.255.255.0

1b. configure the default gateway and disable the dynamic link-local (DHCP network) address in /etc/sysconfig/network
Note: ent 6 defaults to/prefers quotes around the params, i.e. GATEWAY="172.100.130.1"

GATEWAY=172.100.130.1
NOZEROCONF=yes

2. configure hostname 2a. set the FQDN hostname in /etc/sysconfig/network

HOSTNAME=ks-c7a.lab.example.com

2b. set the domain in /etc/resolv.conf

domain lab.example.com

2c. set the IP and hostname info in /etc/hosts (required for 'hostname -s' and other types of resolution)

172.100.200.140   ks-c7a.lab.example.com ks-c7a

3. configure the DNS servers in /etc/resolv.conf (use DNS servers appropriate for your internet provider, for your own internal network, or for your local data center)

nameserver 172.100.170.90
nameserver 172.100.130.90

4. optional, list interface info

Ent 5 or older
# ifconfig
Ent 6
# ip addr

Changing the IP (ent 7)

1. set the new IP and netmask
Note: if the IP is not getting set, please check or go through the Network Setup steps (above), specifically see the note on the default setting with DHCP/manual mode

# nmcli con mod eno16777728 ipv4.addresses 172.100.200.140/24 ipv4.gateway 172.100.200.1
OR
# nmcli con mod eno16777728 ipv4.addresses 172.100.200.140/24
# nmcli con mod eno16777728 ipv4.gateway 172.100.200.1

2. restart networking
Note: this has worked remotely over ssh, as long as the two commands are entered together as per this example, otherwise doing the single down command will cause you to lose your connection and require console access to resolve/fix

# nmcli con down eno16777728 ; nmcli con up eno16777728

Changing the IP (before ent 7)

1. set the new IP and netmask in the ifcfg-interface file (usually ifcfg-eth0) under /etc/sysconfig/network-scripts/
Note: ent 6 defaults to/prefers quotes around the params, i.e. NETMASK="255.255.255.0", ent 6 also introduced CIDR notation, ex; PREFIX="24" to replace the old/longer netmask convention (NETMASK="255.255.255.0")

IPADDR=172.200.110.140
NETMASK=255.255.255.0

2. set the new default gateway in /etc/sysconfig/network
Note: ent 6 defaults to/prefers quotes around the params, i.e. GATEWAY="172.100.130.1"

GATEWAY=172.100.130.1

3. set the IP info in /etc/hosts (required for 'hostname -s' and other types of resolution)

172.100.200.140   ks-c7a.lab.example.com ks-c7a

4. restart networking
Note: recommended to use "&" when connected remotely so the command will continue after the network gets disconnected (your session is normally not lost in this case, and you would normally stay connected)

# service network restart &

Adding Additional IP's/Aliases (ent 7)

1. add the additional IP

# nmcli con mod eno16777728 +ipv4.addresses 172.100.200.140/24

2. restart networking
Note: this has worked remotely over ssh, as long as the two commands are entered together as per this example, otherwise doing the single down command will cause you to lose your connection and require console access to resolve/fix

# nmcli con down eno16777728 ; nmcli con up eno16777728

Adding Additional IP's/Aliases (before ent 7)

1. create an ifcfg-interface:aliasnumber file in /etc/sysconfig/network-scripts/ (ifcfg-eth0:0 for this example), with the following contents

DEVICE="eth0:0"
IPADDR="172.100.200.140"
NETMASK="255.255.255.0"
ONPARENT="yes"

2. restart networking
Note: recommended to use & when connected remotely so the command will continue after the network gets disconnected (your session is normally not lost in this case, and you would normally stay connected)

# service network restart &

Adding Static Routes (ent 7)

Set the address range and gateway address (saved in a route-interface file in /etc/sysconfig/network-scripts/, in this example; route-eno16777728)

# nmcli con mod eno16777728 ipv4.routes "172.200.210.0/24 172.200.210.120"

Adding Static Routes (before ent 7)

Create a route-interface file (for IPv4), example /etc/sysconfig/network-scripts/route-eth0 (or route-bond0 for a bonding interface);

ADDRESS0=172.200.210.0
NETMASK0=255.255.255.0
GATEWAY0=172.200.210.120

Quick Reference

past what is shown above, here are a few additional/helpful commands

Show IP Info (before ent 6)

# ifconfig

Show IP Info (ent 6 and newer)

# ip addr

Show IP Configuration (before ent 7)

# cat /etc/sysconfig/network /etc/sysconfig/network-scripts/ifcfg-e*

Show IP Configuration (ent 7)
Note: run 'nmcli dev' to find the device name

# nmcli dev
DEVICE  TYPE      STATE      CONNECTION
ens32   ethernet  connected  ens32
lo      loopback  unmanaged  --
# nmcli con show ens32

Show Listening Ports (only)
Note: the : in the output normally denotes a listening port

# lsof -nP | grep ":"

Show Network Connections (before ent 7)

# netstat -an

Show Network Connections (ent 7)

# ss -an