BGP zum Provider 1 funktioniert im Unterschied zum Provider 2nicht:
Ursache: Der Status ist nicht established sondern „nur“ connect
Check BGP Provider1:
userc@router1> show bgp summary Groups: 2 Peers: 2 Down peers: 2 Peer AS InPkt OutPkt OutQ Flaps Last Up/Dwn State|#Active/Received/Accepted/Damped... 18.104.22.168 62460 0 0 0 0 32:40 Active 22.214.171.124 3320 0 0 0 0 32:40 Active
Check BGP Provider2:
user@router2> show bgp summary Groups: 2 Peers: 2 Down peers: 1 Peer AS InPkt OutPkt OutQ Flaps Last Up/Dwn State|#Active/Received/Accepted/Damped... 126.96.36.199 196714 16223 18286 0 21 5d 17:12:17 Establ WAN.inet.0: 1/1/1/0 188.8.131.52 62460 72 72 0 3 1w2d22h Active
Routing neu starten
Restart Routing immidiately|gracefully
Check BGP State
Current state of the BGP session:
- Active—BGP is initiating a transport protocol connection in an attempt to connect to a peer. If the connection is successful, BGP sends an open message.
- Connect—BGP is waiting for the transport protocol connection to complete.
- Established—The BGP session has been established, and the peers are exchanging update messages.
- Idle—Either the BGP license checkfailed, or this is the first stage of a connection and BGP is waiting for a Start event.
- OpenConfirm—BGP has acknowledged receipt of an open message from the peer and is waiting to receive a keepalive or notification message.
- OpenSent—BGP has sent an open message and is waiting to receive an open message from the peer.
Wir haben als ein Problem mit der TCP Verbindung:
show interfaces ge-4/0/0 Physical interface: ge-4/0/0, Enabled, Physical link is Up Interface index: 160, SNMP ifIndex: 551 Description: WAN-DTAG-ADVA-LWL-Port-1 Link-level type: Ethernet, MTU: 1514, Link-mode: Full-duplex, Speed: 1000mbps, BPDU Error: None, MAC-REWRITE Error: None, Loopback: Disabled, Source filtering: Disabled, Flow control: Enabled, Auto-negotiation: Enabled, Remote fault: Online Device flags : Present Running Interface flags: SNMP-Traps Internal: 0x0 Link flags : None CoS queues : 8 supported, 8 maximum usable queues Current address: 3c:61:04:8f:ff:64, Hardware address: 3c:61:04:8f:ff:64 Last flapped : 2014-04-18 20:07:12 UTC (00:03:31 ago) Input rate : 0 bps (0 pps) Output rate : 0 bps (0 pps) Active alarms : None Active defects : None Interface transmit statistics: Disabled Logical interface ge-4/0/0.0 (Index 84) (SNMP ifIndex 560) Flags: SNMP-Traps 0x0 Encapsulation: ENET2 Input packets : 0 Output packets: 480 Security: Zone: Null Protocol inet, MTU: 1500 Flags: Sendbcast-pkt-to-re, Is-Primary Addresses, Flags: Is-Preferred Is-Primary Destination: 184.108.40.206/30, Local: 220.127.116.11, Broadcast: 18.104.22.168
Näheres verrät die Info über die BGP Neighbours:
show bgp neigbours Peer: 22.214.171.124+179 AS 3320 Local: 126.96.36.199 AS 62460 Type: External State: Connect Flags: <ImportEval> Last State: Connect Last Event: ConnectRetry Last Error: None Export: [ AS3320_v4_EXPORT ] Import: [ AS3320_v4_IMPORT ] Options: <Preference LocalAddress AuthKey PeerAS Refresh> Authentication key is configured Local Address: 188.8.131.52 Holdtime: 90 Preference: 100 Number of flaps: 0 Trace options: open, update Trace file: /var/log/WAN-bgp size 0 files 10
user@router1> show bgp replication Synchronization master: Session state: Down, Since: 28:25 Flaps: 0 Protocol state: Idle, Since: 28:25 Synchronization state: NotStarted Number of peers waiting: AckWait: 0, SoWait: 0, Scheduled: 0 Messages sent: Open 0, Establish 0, Update 0, Error 0, Complete 0 Messages received: Open 0, Request 0 wildcard 0 targeted, EstablishAck 0, CompleteAck 0
ACTIVE and CONNECT are basically TCP States
BGP relies on the TCP protocol for transport. So TCP must be established first before BGP can proceed, hence these different states.
I have found many different explanations and here is one, I concocted. Both states are trying to acomplish the same thing, but are a result of diffent things happening.
The CONNECT state is the the result of a start event, which can be an automated event or one done by an Admin- maybe he just configured BGP on an interface and hit the commit button. Once the start even is sent, BGP kicks its resources into gear and trys to establish the TCP session, then transition to the CONNECT state.
In the CONNECT state it is waiting for response from the peer to complete the 3-way handshake, TCP Connection.
Among other things it starts a ConnectRetryTimer. If the connection is successful, it sends the OPEN message to the peer, then transitions to the OPENSENT state.
If there are TCP ERRORS resulting in a failure, it closes the connection and goes back to IDLE
If the connection is unsuccessful during the connect state and the retry timer has expired, transitions to ACTIVE state and tries to re-establish the TCP session again. And if successful, then OPEN message is sent and it transitions to OPENSENT…