Configuring Networking

Each provisioning type requires some network configuration. Use this chapter to configure network services in your integrated orcharhino Proxy on orcharhino Server.

New hosts must have access to your orcharhino Proxy. orcharhino Proxy can be either your integrated orcharhino Proxy on orcharhino Server or an external orcharhino Proxy. You might want to provision hosts from an external orcharhino Proxy when the hosts are on isolated networks and cannot connect to orcharhino Server directly, or when the content is synchronized with orcharhino Proxy. Provisioning using the external orcharhino Proxy can save on network bandwidth.

Configuring orcharhino Proxy has two basic requirements:

  1. Configuring network services. This includes:

    • Content delivery services

    • Network services (DHCP, DNS, and TFTP)

    • Puppet configuration

  2. Defining network resource data in orcharhino Server to help configure network interfaces on new hosts.

The following instructions have similar applications to configuring standalone orcharhino Proxies managing a specific network.

Network Resources

orcharhino contains networking resources that you must set up and configure to create a host. It includes the following networking resources:

Domain

You must assign every host that is managed by orcharhino to a domain. Using the domain, orcharhino can manage A, AAAA, and PTR records. Even if you do not want orcharhino to manage your DNS servers, you still must create and associate at least one domain. Domains are included in the naming conventions orcharhino hosts, for example, a host with the name test123 in the example.com domain has the fully qualified domain name test123.example.com.

Subnet

You must assign every host managed by orcharhino to a subnet. Using subnets, orcharhino can then manage IPv4 reservations. If there are no reservation integrations, you still must create and associate at least one subnet. When you manage a subnet in orcharhino, you cannot create DHCP records for that subnet outside of orcharhino. In orcharhino, you can use IP Address Management (IPAM) to manage IP addresses with one of the following options:

  • DHCP: DHCP orcharhino Proxy manages the assignment of IP addresses by finding the next available IP address starting from the first address of the range and skipping all addresses that are reserved. Before assigning an IP address, orcharhino Proxy sends an ICMP and TCP pings to check whether the IP address is in use. Note that if a host is powered off, or has a firewall configured to disable connections, orcharhino makes a false assumption that the IP address is available. This check does not work for hosts that are turned off, therefore, the DHCP option can only be used with subnets that orcharhino controls and that do not have any hosts created externally.

    The orcharhino Proxy DHCP module retains the offered IP addresses for a short period of time to prevent collisions during concurrent access, so some IP addresses in the IP range might remain temporarily unused.

  • Internal DB: orcharhino finds the next available IP address from the Subnet range by excluding all IP addresses from the orcharhino database in sequence. The primary source of data is the database, not DHCP reservations. This IPAM is not safe when multiple hosts are being created in parallel; in that case, use DHCP or Random DB IPAM instead.

  • Random DB: orcharhino finds the next available IP address from the Subnet range by excluding all IP addresses from the orcharhino database randomly. The primary source of data is the database, not DHCP reservations. This IPAM is safe to use with concurrent host creation as IP addresses are returned in random order, minimizing the chance of a conflict.

  • EUI-64: Extended Unique Identifier (EUI) 64bit IPv6 address generation, as per RFC2373, is obtained through the 48-bit MAC address.

  • External IPAM: Delegates IPAM to an external system through orcharhino Proxy feature. orcharhino currently does not ship with any external IPAM implementations, but several plug-ins are in development.

  • None: IP address for each host must be entered manually.

    Options DHCP, Internal DB and Random DB can lead to DHCP conflicts on subnets with records created externally. These subnets must be under exclusive orcharhino control.

    For more information about adding a subnet, see Adding a Subnet to Server.

DHCP Ranges

You can define the same DHCP range in orcharhino Server for both discovered and provisioned systems, but use a separate range for each service within the same subnet.

orcharhino and DHCP Options

orcharhino manages DHCP reservations through a DHCP orcharhino Proxy. orcharhino also sets the next-server and filename DHCP options.

The next-server option

The next-server option provides the IP address of the TFTP server to boot from. This option is not set by default and must be set for each TFTP orcharhino Proxy. You can use the foreman-installer command with the --foreman-proxy-tftp-servername option to set the TFTP server in the /etc/foreman-proxy/settings.d/tftp.yml file:

# foreman-installer --foreman-proxy-tftp-servername 1.2.3.4

Each TFTP orcharhino Proxy then reports this setting through the API and orcharhino can retrieve the configuration information when it creates the DHCP record.

When the PXE loader is set to none, orcharhino does not populate the next-server option into the DHCP record.

If the next-server option remains undefined, orcharhino uses reverse DNS search to find a TFTP server address to assign, but you might encounter the following problems:

  • DNS timeouts during provisioning

  • Querying of incorrect DNS server. For example, authoritative rather than caching

  • Errors about incorrect IP address for the TFTP server. For example, PTR record was invalid

If you encounter these problems, check the DNS setup on both orcharhino and orcharhino Proxy, specifically the PTR record resolution.

The filename option

The filename option contains the full path to the file that downloads and executes during provisioning. The PXE loader that you select for the host or host group defines which filename option to use. When the PXE loader is set to none, orcharhino does not populate the filename option into the DHCP record. Depending on the PXE loader option, the filename changes as follows:

PXE loader option filename entry Notes

PXELinux BIOS

pxelinux.0

PXELinux UEFI

pxelinux.efi

iPXE Chain BIOS

undionly.kpxe

PXEGrub2 UEFI

grub2/grubx64.efi

x64 can differ depending on architecture

iPXE UEFI HTTP

\http://orcharhino-proxy.example.com:8000/httpboot/ipxe-x64.efi

Requires the httpboot feature and renders the filename as a full URL where orcharhino-proxy.example.com is a known host name of orcharhino Proxy in orcharhino.

Grub2 UEFI HTTP

\http://orcharhino-proxy.example.com:8000/httpboot/grub2/grubx64.efi

Requires the httpboot feature and renders the filename as a full URL where orcharhino-proxy.example.com is a known host name of orcharhino Proxy in orcharhino.

Troubleshooting DHCP Problems in orcharhino

orcharhino can manage an ISC DHCP server on internal or external DHCP orcharhino Proxy. orcharhino can list, create, and delete DHCP reservations and leases. However, there are a number of problems that you might encounter on occasions.

Out of sync DHCP records

When an error occurs during DHCP orchestration, DHCP records in the orcharhino database and the DHCP server might not match. To fix this, you must add missing DHCP records from the orcharhino database to the DHCP server and then remove unwanted records from the DHCP server as per the following steps:

Procedure
  1. To preview the DHCP records that are going to be added to the DHCP server, enter the following command:

    # foreman-rake orchestration:dhcp:add_missing subnet_name=NAME
  2. If you are satisfied by the preview changes in the previous step, apply them by entering the above command with the perform=1 argument:

    # foreman-rake orchestration:dhcp:add_missing subnet_name=NAME perform=1
  3. To keep DHCP records in orcharhino and in the DHCP server synchronized, you can remove unwanted DHCP records from the DHCP server. Note that orcharhino assumes that all managed DHCP servers do not contain third-party records, therefore, this step might delete those unexpected records. To preview what records are going to be removed from the DHCP server, enter the following command:

    # foreman-rake orchestration:dhcp:remove_offending subnet_name=NAME
  4. If you are satisfied by the preview changes in the previous step, apply them by entering the above command with the perform=1 argument:

    # foreman-rake orchestration:dhcp:remove_offending subnet_name=NAME perform=1
PXE loader option change

When the PXE loader option is changed for an existing host, this causes a DHCP conflict. The only workaround is to overwrite the DHCP entry.

Incorrect permissions on DHCP files

An operating system update can update the dhcpd package. This causes the permissions of important directories and files to reset so that the DHCP orcharhino Proxy cannot read the required information.

Changing the DHCP orcharhino Proxy entry

orcharhino manages DHCP records only for hosts that are assigned to subnets with a DHCP orcharhino Proxy set. If you create a host and then clear or change the DHCP orcharhino Proxy, when you attempt to delete the host, the action fails.

If you create a host without setting the DHCP orcharhino Proxy and then try to set the DHCP orcharhino Proxy, this causes DHCP conflicts.

Deleted hosts entries in the dhcpd.leases file

Any changes to a DHCP lease are appended to the end of the dhcpd.leases file. Because entries are appended to the file, it is possible that two or more entries of the same lease can exist in the dhcpd.leases file at the same time. When there are two or more entries of the same lease, the last entry in the file takes precedence. Group, subgroup and host declarations in the lease file are processed in the same manner. If a lease is deleted, { deleted; } is appended to the declaration.

Prerequisites for Image Based Provisioning

Post-Boot Configuration Method

Images that use the finish post-boot configuration scripts require a managed DHCP server, such as orcharhino’s integrated orcharhino Proxy or an external orcharhino Proxy. The host must be created with a subnet associated with a DHCP orcharhino Proxy, and the IP address of the host must be a valid IP address from the DHCP range.

It is possible to use an external DHCP service, but IP addresses must be entered manually. The SSH credentials corresponding to the configuration in the image must be configured in orcharhino to enable the post-boot configuration to be made.

Check the following items when troubleshooting a virtual machine booted from an image that depends on post-configuration scripts:

  • The host has a subnet assigned in orcharhino Server.

  • The subnet has a DHCP orcharhino Proxy assigned in orcharhino Server.

  • The host has a valid IP address assigned in orcharhino Server.

  • The IP address acquired by the virtual machine using DHCP matches the address configured in orcharhino Server.

  • The virtual machine created from an image responds to SSH requests.

  • The virtual machine created from an image authorizes the user and password, over SSH, which is associated with the image being deployed.

  • orcharhino Server has access to the virtual machine via SSH keys. This is required for the virtual machine to receive post-configuration scripts from orcharhino Server.

Pre-Boot Initialization Configuration Method

Images that use the cloud-init scripts require a DHCP server to avoid having to include the IP address in the image. A managed DHCP orcharhino Proxy is preferred. The image must have the cloud-init service configured to start when the system boots and fetch a script or configuration data to use in completing the configuration.

Check the following items when troubleshooting a virtual machine booted from an image that depends on initialization scripts included in the image:

  • There is a DHCP server on the subnet.

  • The virtual machine has the cloud-init service installed and enabled.

Configuring Network Services

Some provisioning methods use orcharhino Proxy services. For example, a network might require orcharhino Proxy to act as a DHCP server. A network can also use PXE boot services to install the operating system on new hosts. This requires configuring orcharhino Proxy to use the main PXE boot services: DHCP, DNS, and TFTP.

Use the foreman-installer command with the options to configure these services on orcharhino Server.

To configure these services on an external orcharhino Proxy, run foreman-installer --no-enable-foreman. For more information, see Installing orcharhino Proxy Guide.

Procedure
  1. Enter the foreman-installer command to configure the required network services:

    # foreman-installer --foreman-proxy-dhcp true \
    --foreman-proxy-dhcp-gateway "192.168.140.1" \
    --foreman-proxy-dhcp-interface "eth1" \
    --foreman-proxy-dhcp-managed true \
    --foreman-proxy-dhcp-nameservers "192.168.140.2" \
    --foreman-proxy-dhcp-range "192.168.140.10 192.168.140.110" \
    --foreman-proxy-dhcp-server "192.168.140.2" \
    --foreman-proxy-dns true \
    --foreman-proxy-dns-forwarders "8.8.8.8; 8.8.4.4" \
    --foreman-proxy-dns-interface "eth1" \
    --foreman-proxy-dns-managed true \
    --foreman-proxy-dns-reverse "140.168.192.in-addr.arpa" \
    --foreman-proxy-dns-server "127.0.0.1" \
    --foreman-proxy-dns-zone "example.com" \
    --foreman-proxy-tftp true \
    --foreman-proxy-tftp-managed true
  2. Find orcharhino Proxy that you configure:

    # hammer proxy list
  3. Refresh features of orcharhino Proxy to view the changes:

    # hammer proxy refresh-features --name "orcharhino.example.com"
  4. Verify the services configured on orcharhino Proxy:

    # hammer proxy info --name "orcharhino.example.com"

Multiple Subnets or Domains Using Installer

The foreman-installer options allow only for a single DHCP subnet or DNS domain. One way to define more than one subnet is by using a custom configuration file.

For every additional subnet or domain, create an entry in /etc/foreman-installer/custom-hiera.yaml file:

dhcp::pools:
 isolated.lan:
   network: 192.168.99.0
   mask: 255.255.255.0
   gateway: 192.168.99.1
   range: 192.168.99.5 192.168.99.49

dns::zones:
  # creates @ SOA $::fqdn root.example.com.
  # creates $::fqdn A $::ipaddress
  example.com: {}

  # creates @ SOA test.example.net. hostmaster.example.com.
  # creates test.example.net A 192.0.2.100
  example.net:
    soa: test.example.net
    soaip: 192.0.2.100
    contact: hostmaster.example.com.

  # creates @ SOA $::fqdn root.example.org.
  # does NOT create an A record
  example.org:
    reverse: true

  # creates @ SOA $::fqdn hostmaster.example.com.
  2.0.192.in-addr.arpa:
    reverse: true
    contact: hostmaster.example.com.

Execute foreman-installer to perform the changes and verify that the /etc/dhcp/dhcpd.conf contains appropriate entries. Subnets must be then defined in orcharhino database.

DHCP Options for Network Configuration

--foreman-proxy-dhcp

Enables the DHCP service. You can set this option to true or false.

--foreman-proxy-dhcp-managed

Enables Foreman to manage the DHCP service. You can set this option to true or false.

--foreman-proxy-dhcp-gateway

The DHCP pool gateway. Set this to the address of the external gateway for hosts on your private network.

--foreman-proxy-dhcp-interface

Sets the interface for the DHCP service to listen for requests. Set this to eth1.

--foreman-proxy-dhcp-nameservers

Sets the addresses of the nameservers provided to clients through DHCP. Set this to the address for orcharhino Server on eth1.

--foreman-proxy-dhcp-range

A space-separated DHCP pool range for Discovered and Unmanaged services.

--foreman-proxy-dhcp-server

Sets the address of the DHCP server to manage.

Run foreman-installer --help to view more options related to DHCP and other orcharhino Proxy services.

DNS Options for Network Configuration

--foreman-proxy-dns

Enables DNS service. You can set this option to true or false.

--foreman-proxy-dns-managed

Enables Foreman to manage the DNS service. You can set this option to true or false.

--foreman-proxy-dns-forwarders

Sets the DNS forwarders. Set this to your DNS servers.

--foreman-proxy-dns-interface

Sets the interface to listen for DNS requests. Set this to eth1.

--foreman-proxy-dns-reverse

The DNS reverse zone name.

--foreman-proxy-dns-server

Sets the address of the DNS server to manage.

--foreman-proxy-dns-zone

Sets the DNS zone name.

Run foreman-installer --help to view more options related to DNS and other orcharhino Proxy services.

TFTP Options for Network Configuration

--foreman-proxy-tftp

Enables TFTP service. You can set this option to true or false.

--foreman-proxy-tftp-managed

Enables Foreman to manage the TFTP service. You can set this option to true or false.

--foreman-proxy-tftp-servername

Sets the TFTP server to use. Ensure that you use orcharhino Proxy’s IP address.

Run foreman-installer --help to view more options related to TFTP and other orcharhino Proxy services.

Using TFTP Services Through NAT

You can use orcharhino TFTP services through NAT. To do this, on all NAT routers or firewalls, you must enable a TFTP service on UDP port 69 and enable the TFTP state tracking feature. For more information, see the documentation for your NAT device.

Using NAT on Linux with firewalld:
  • Use the following command to allow TFTP service on UDP port 69, load the kernel TFTP state tracking module, and make the changes persistent:

    # firewall-cmd --add-service=tftp && firewall-cmd --runtime-to-permanent
Using NAT on linux with iptables:
  1. Configure the firewall to allow TFTP service UDP on port 69:

    # iptables \
    --sport 69 \
    --state ESTABLISHED \
    -A OUTPUT \
    -i eth0 \
    -j ACCEPT \
    -m state \
    -p udp
    # service iptables save
  2. Load the ip_conntrack_tftp kernel TFTP state module. In the /etc/sysconfig/iptables-config file, locate IPTABLES_MODULES and add ip_conntrack_tftp as follows:

    IPTABLES_MODULES="ip_conntrack_tftp"

Adding a Domain to orcharhino Server

orcharhino Server defines domain names for each host on the network. orcharhino Server must have information about the domain and orcharhino Proxy responsible for domain name assignment.

Checking for Existing Domains

orcharhino Server might already have the relevant domain created as part of orcharhino Server installation. Switch the context to Any Organization and Any Location then check the domain list to see if it exists.

DNS Server Configuration Considerations

During the DNS record creation, orcharhino performs conflict DNS lookups to verify that the host name is not in active use. This check runs against one of the following DNS servers:

  • The system-wide resolver if Administer > Settings > Query local nameservers is set to true.

  • The nameservers that are defined in the subnet associated with the host.

  • The authoritative NS-Records that are queried from the SOA from the domain name associated with the host.

If you experience timeouts during DNS conflict resolution, check the following settings:

  • The subnet nameservers must be reachable from orcharhino Server.

  • The domain name must have a Start of Authority (SOA) record available from orcharhino Server.

  • The system resolver in the /etc/resolv.conf file must have a valid and working configuration.

To use the CLI instead of the orcharhino management UI, see the CLI procedure.

Procedure
  1. In the orcharhino management UI, navigate to Infrastructure > Domains and click Create Domain.

  2. In the DNS Domain field, enter the full DNS domain name.

  3. In the Fullname field, enter the plain text name of the domain.

  4. Click the Parameters tab and configure any domain level parameters to apply to hosts attached to this domain. For example, user defined Boolean or string parameters to use in templates.

  5. Click Add Parameter and fill in the Name and Value fields.

  6. Click the Locations tab, and add the location where the domain resides.

  7. Click the Organizations tab, and add the organization that the domain belongs to.

  8. Click Submit to save the changes.

CLI procedure
  • Use the hammer domain create command to create a domain:

    # hammer domain create \
    --description "My_Domain" \
    --dns-id My_DNS_ID \
    --locations "My_Location" \
    --name "my-domain.tld" \
    --organizations "My_Organization"

In this example, the --dns-id option uses 1, which is the ID of your integrated orcharhino Proxy on orcharhino Server.

Adding a Subnet to orcharhino Server

You must add information for each of your subnets to orcharhino Server because orcharhino configures interfaces for new hosts. To configure interfaces, orcharhino Server must have all the information about the network that connects these interfaces.

To use the CLI instead of the orcharhino management UI, see the CLI procedure.

Procedure
  1. In the orcharhino management UI, navigate to Infrastructure > Subnets, and in the Subnets window, click Create Subnet.

  2. In the Name field, enter a name for the subnet.

  3. In the Description field, enter a description for the subnet.

  4. In the Network address field, enter the network address for the subnet.

  5. In the Network prefix field, enter the network prefix for the subnet.

  6. In the Network mask field, enter the network mask for the subnet.

  7. In the Gateway address field, enter the external gateway for the subnet.

  8. In the Primary DNS server field, enter a primary DNS for the subnet.

  9. In the Secondary DNS server, enter a secondary DNS for the subnet.

  10. From the IPAM list, select the method that you want to use for IP address management (IPAM). For more information about IPAM, see Configuring Networking.

  11. Enter the information for the IPAM method that you select.

  12. If you use the remote execution plugin, click the Remote Execution tab and select the orcharhino Proxy that controls the remote execution.

  13. Click the Domains tab and select the domains that apply to this subnet.

  14. Click the orcharhino Proxies tab and select the orcharhino Proxy that applies to each service in the subnet, including DHCP, TFTP, and reverse DNS services.

  15. Click the Parameters tab and configure any subnet level parameters to apply to hosts attached to this subnet. For example, user defined Boolean or string parameters to use in templates.

  16. Click the Locations tab and select the locations that use this orcharhino Proxy.

  17. Click the Organizations tab and select the organizations that use this orcharhino Proxy.

  18. Click Submit to save the subnet information.

CLI procedure
  • Create the subnet with the following command:

    # hammer subnet create \
    --boot-mode "DHCP" \
    --description "My_Description" \
    --dhcp-id My_DHCP_ID \
    --dns-id My_DNS_ID \
    --dns-primary "192.168.140.2" \
    --dns-secondary "8.8.8.8" \
    --domains "my-domain.tld" \
    --from "192.168.140.111" \
    --gateway "192.168.140.1" \
    --ipam "DHCP" \
    --locations "_My_Location" \
    --mask "255.255.255.0" \
    --name "My_Network" \
    --network "192.168.140.0" \
    --organizations "My_Organization"
    --tftp-id My_TFTP_ID \
    --to "192.168.140.250" \

In this example, the --dhcp-id, --dns-id, and --tftp-id options use 1, which is the ID of the integrated orcharhino Proxy in orcharhino Server.

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