Class: Distem::Lib::NetTools

Inherits:
Object
  • Object
show all
Defined in:
lib/distem/distemlib/nettools.rb

Overview

Class that allow to perform physical operations on a physical network resource

Constant Summary

DEFAULT_BRIDGE =

Name used for the bridge set up on a physical machine

'br0'
VXLAN_BRIDGE_PREFIX = 
'vxlanbr'
VXLAN_INTERFACE_PREFIX = 
'vxlan'
LOCALHOST =

:nodoc:

'localhost'
IFNAMEMAXSIZE =

Maximal size for a network interface name (from GNU/Linux specifications)

15
@@nic_count = 
1
@@addr_default = 
nil
@@br_info =

Hash containing the (interface name, interface address, interface netmask) triplet for a root interface on which a bridge is plugged on

{}

Class Method Summary (collapse)

Instance Method Summary (collapse)

Class Method Details

+ (Object) create_vxlan_interface(id, mcast_id, address, netmask, root_interface)

Create a VXLAN interface to encapsulate inter-pnode traffic inside VXLAN tunnel

Attributes

  • id identifier of the VXLAN

  • mcast_id identifier used to generate the address of the multicast group

  • address address of the related virtual network

  • netmask netmask of the related virtual network

  • default_interface specify a default interface used to plug the VXLAN interface



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# File 'lib/distem/distemlib/nettools.rb', line 259

def self.create_vxlan_interface(id, mcast_id, address,netmask,root_interface)
  vxlan_iface = VXLAN_INTERFACE_PREFIX + id.to_s
  bridge = VXLAN_BRIDGE_PREFIX + id.to_s
  # First, we set up the VXLAN interface
  mcast_addr = IPAddress::IPv4::parse_u32(mcast_id + IPAddress("239.0.0.0").u32).address
  Shell.run("ip link add #{vxlan_iface} type vxlan id #{id} group #{mcast_addr} ttl 10 dev #{root_interface} dstport 4789")
  Shell.run("ip link set up dev #{vxlan_iface}")
  # Then, we create a bridge
  Shell.run("brctl addbr #{bridge}")
  Shell.run("brctl setfd #{bridge} 0")
  Shell.run("brctl setageing #{bridge} 3000000")
  Shell.run("/bin/ip link set dev #{bridge} promisc on")
  Shell.run("/bin/ip link set dev #{bridge} up")
  # And we add the VXLAN interface into the bridge
  Shell.run("brctl addif #{bridge} #{vxlan_iface}")
  Shell.run("ifconfig #{vxlan_iface} 0.0.0.0 up")
end

+ (Object) disable_ipv6

Disable IPv6



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# File 'lib/distem/distemlib/nettools.rb', line 167

def self.disable_ipv6()
  Shell.run('sysctl -w net.ipv6.conf.all.disable_ipv6=1; true')
end

+ (Object) get_default_addr(cache = true)

Gets the IP address of the default network interface used for network communications

Returns

String object



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# File 'lib/distem/distemlib/nettools.rb', line 69

def self.get_default_addr(cache=true)
  if !@@addr_default or !cache
    iface = self.get_default_iface()
    @@addr_default = self.get_iface_addr(iface).strip
  end
  return @@addr_default
end

+ (Object) get_default_gateway

Gets the IP address of the default gateway

Returns

String object



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# File 'lib/distem/distemlib/nettools.rb', line 80

def self.get_default_gateway
  cmdret = Shell.run("/bin/ip route list")
  return cmdret.lines.grep(/^default /).first.gsub(/.* via ([0-9.]+).*/, '\1').chomp
end

+ (Object) get_default_iface

Gets the name of the default network interface used for network communications

Returns

String object



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# File 'lib/distem/distemlib/nettools.rb', line 23

def self.get_default_iface
  defroute = Shell.run("/bin/ip route list").split(/\n/).grep(/^default /)
  if defroute.empty?
    return ""
  else
    return defroute[0].gsub(/.* dev ([^\s]+)( .*)?/, '\1')
  end
end

+ (Object) get_iface_addr(iface)

Gets the IP address of a specified network interface

Attributes

  • iface The network interface name (String)

Returns

String object



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# File 'lib/distem/distemlib/nettools.rb', line 48

def self.get_iface_addr(iface)
  cmdret = Shell.run("/sbin/ifconfig #{iface}")
  # | grep 'inet addr' | awk '{print \$2}' | cut -d':' -f2 | tr -d '\n'")
  ret=""
  cmdret.each_line { |s| ret=s.split[1].split(":")[1] if s.include?("inet addr") }
  return ret
end

+ (Object) get_iface_config(iface)

Gets the inet interface configuration in a form suitable for 'ip addr add'

Attributes

  • iface The network interface name (String)

Returns

String object



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# File 'lib/distem/distemlib/nettools.rb', line 62

def self.get_iface_config(iface)
  return Shell.run("/bin/ip addr show dev #{iface}").split(/\n/).grep(/inet /)[0].gsub(/.*inet ([^\s]+ brd [^\s]+).*/, '\1').chomp
end

+ (Object) get_iface_mtu(vnode, viface)

Gets the current MTU of a virtual network interface

Attributes

  • vnode The VNode object

  • viface The VIface object

Returns

Integer object



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# File 'lib/distem/distemlib/nettools.rb', line 206

def self.get_iface_mtu(vnode,viface)
  iface = "#{vnode.name}-#{viface.name}-#{viface.id}"
  cmdret = Shell.run("/sbin/ifconfig #{iface}")
  return cmdret.split("\n").grep(/.*MTU.*/)[0].gsub(/.*MTU:(\d+) .*/, '\1').to_i
end

+ (Object) get_iface_name(vnode, viface)

Gets the physical name of a virtual network interface

Attributes

  • vnode The VNode object

  • viface The VIface object

Returns

String object



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# File 'lib/distem/distemlib/nettools.rb', line 189

def self.get_iface_name(vnode,viface)
  # >>> TODO: Remove vnode parameter)
  raise unless vnode.is_a?(Resource::VNode)
  raise unless viface.is_a?(Resource::VIface)

  ret = "#{vnode.name}-#{viface.name}-#{viface.id}"
  binf = (ret.size >= IFNAMEMAXSIZE ? ret.size-IFNAMEMAXSIZE : 0)
  ret = ret[binf..ret.size]
end

+ (Object) get_netmask(iface)

Get the netmask of an interface

Attributes

  • iface The network interface name (String)

Returns

String object



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# File 'lib/distem/distemlib/nettools.rb', line 37

def self.get_netmask(iface)
  cmd = Shell.run("ifconfig #{iface}")
  return cmd.split(/\n/).grep(/Mask/).first.gsub(/.*Mask:(.*)$/,'\1')
end

+ (Boolean) localaddr?(address)

Check if an IP address is local to this physical node

Attributes

  • address The IP address (String)

Returns

Boolean value

Returns:

  • (Boolean) 


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# File 'lib/distem/distemlib/nettools.rb', line 218

def self.localaddr?(address)
  raise unless address.is_a?(String)

  begin
    target = Resolv.getaddress(address)
  rescue Resolv::ResolvError
    raise Lib::InvalidParameterError, address
  end

  #Checking if the address is the loopback
  begin
    ret = (Resolv.getnames(target).include?(LOCALHOST))
  rescue Resolv::ResolvError
    ret = false
  end

  ret = (target == LOCALHOST) unless ret

  #Checking if the address is the one of the default interface
  ret = (Lib::NetTools.get_default_addr == target) unless ret

  #Checking if the address is the one of the ip associated with the hostname of the machine
  unless ret
    begin
      ret = (Resolv.getaddress(Socket.gethostname) == target)
    rescue Resolv::ResolvError
      ret = false
    end
  end

  return ret
end

+ (Object) remove_vxlan_interface(id)

Remove a VXLAN interface and its related bridge

Attributes

  • id identifier of the VXLAN



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# File 'lib/distem/distemlib/nettools.rb', line 280

def self.remove_vxlan_interface(id)
  vxlan_iface = VXLAN_INTERFACE_PREFIX + id.to_s
  bridge = VXLAN_BRIDGE_PREFIX + id.to_s
  Shell.run("brctl delif #{bridge} #{vxlan_iface}")
  Shell.run("ip link del #{vxlan_iface}")
  Shell.run("ifconfig #{bridge} down")
  Shell.run("brctl delbr #{bridge}")
end

+ (Object) set_arp_cache

Set up the ARP cache



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# File 'lib/distem/distemlib/nettools.rb', line 140

def self.set_arp_cache()
  Shell.run("sysctl -w net.ipv4.neigh.default.base_reachable_time=86400")
  Shell.run("sysctl -w net.ipv4.neigh.default.gc_stale_time=86400")
  Shell.run("sysctl -w net.ipv4.neigh.default.gc_thresh1=100000000")
  Shell.run("sysctl -w net.ipv4.neigh.default.gc_thresh2=100000000")
  Shell.run("sysctl -w net.ipv4.neigh.default.gc_thresh3=100000000")
end

+ (Object) set_bridge(root_interface, default_gw) 



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# File 'lib/distem/distemlib/nettools.rb', line 85

def self.set_bridge(root_interface, default_gw)
  str = Shell.run("ifconfig")
  bridge_name = "br_#{root_interface}"
  unless str.include?(bridge_name)
    @@br_info[bridge_name] = [root_interface, self.get_iface_addr(root_interface), self.get_netmask(root_interface)]
    # needs to be done before we break eth0
    cfg = self.get_iface_config(root_interface)
    Shell.run("ethtool -G #{root_interface} rx 4096 tx 4096 || true")

    Shell.run("brctl addbr #{bridge_name}")
    Shell.run("brctl setfd #{bridge_name} 0")
    Shell.run("brctl setageing #{bridge_name} 3000000")
    Shell.run("/bin/ip addr add dev #{bridge_name} #{cfg}")
    Shell.run("/bin/ip link set dev #{bridge_name} promisc on")
    Shell.run("/bin/ip link set dev #{bridge_name} up")
    Shell.run("brctl addif #{bridge_name} #{root_interface}")
    Shell.run("ifconfig #{root_interface} 0.0.0.0 up")
    # Set the default route only if the default interface has been added into the bridge, in
    # this case the default gateway is passed as a parameter to set_bridge
    if default_gw
      iface = self.get_default_iface()
      unless iface.empty?
        Shell.run("ip route del default dev #{iface}")
      end
      Shell.run("ip route add default dev #{bridge_name} via #{default_gw}")
    end
    return bridge_name
  else
    return nil
  end
end

+ (Object) set_ifb(nb = 64)

Set up the IFB module



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# File 'lib/distem/distemlib/nettools.rb', line 135

def self.set_ifb(nb=64)
  Shell.run("modprobe ifb numifbs=#{nb}")
end

+ (Object) set_new_nic(address, netmask, iface)

Create a new NIC network interface on the physical node (used to communicate with the VNodes, see Daemon::Admin)



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# File 'lib/distem/distemlib/nettools.rb', line 154

def self.set_new_nic(address,netmask,iface)
  new_iface = "#{iface}:#{@@nic_count}"
  Shell.run("ifconfig #{new_iface} #{address} netmask #{netmask}")
  @@nic_count += 1
  return new_iface
end

+ (Object) set_resource(max_vifaces, set_bridge)

Set up a physical machine network properties

Attributes

  • max_vifaces the maximum number of virtual network interfaces that'll be set on this physical machine

  • set_bridge boolean specifying if a bridge has to be created



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# File 'lib/distem/distemlib/nettools.rb', line 175

def self.set_resource(max_vifaces,set_bridge)
  disable_ipv6()
  set_arp_cache()
  set_bridge() if set_bridge
  set_ifb(max_vifaces)
end

+ (Object) unset_bridge(brname, default_gw)

Unset the bridge and restore the default interface, if possible



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# File 'lib/distem/distemlib/nettools.rb', line 118

def self.unset_bridge(brname, default_gw)
  interface, ip, netmask = @@br_info[brname]
  @@br_info.delete(brname)
  cmd = ""
  Dir.glob("/sys/class/net/#{brname}/brif/*").each { |i|
    cmd += "brctl delif #{brname} #{File.basename(i)};"
  }
  cmd += "ip link set #{brname} down;"
  cmd += "brctl delbr #{brname};"
  cmd += "ifconfig #{interface} #{ip} netmask #{netmask}"
  if default_gw
    cmd += ";route add -net 0.0.0.0 gw #{default_gw} dev #{interface}"
  end
  Shell.run(cmd)
end

+ (Object) unset_ifb

Clean the IFB module



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# File 'lib/distem/distemlib/nettools.rb', line 149

def self.unset_ifb()
  Shell.run("rmmod ifb")
end

+ (Object) unset_nic(name)

Unset NIC



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# File 'lib/distem/distemlib/nettools.rb', line 162

def self.unset_nic(name)
  Shell.run("ifconfig #{name} down")
end

Instance Method Details

- (Object) DELETE brname 



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# File 'lib/distem/distemlib/nettools.rb', line 120

@@br_info.delete(brname)