[f-nsp] Limitation in number of bgp-communities leads to closure ofbgp-session - possible bug?

[Gunther Stammwitz]

Hello Daniel,


Thanks for the notice. So I'm not the only one....

Did you open a ticket with the foundry tac/support?
I've done so this morning and am waiting for reply.

Regards,
Gunther 

> -----Ursprüngliche Nachricht-----
> Von: Daniel van Wijnen [mailto:Daniel at rokscom.nl] 
> Gesendet: Donnerstag, 5. Oktober 2006 11:18
> An: Gunther Stammwitz; foundry-nsp at puck.nether.net
> Betreff: RE: [f-nsp] Limitation in number of bgp-communities 
> leads to closure ofbgp-session - possible bug?
> 
> Hi Gunther,
> 
> We saw the same problem on an IBGP session between a M20 (route
> reflector) and a Jetcore BI configured as rr client.
> 
> 
> Regards,
> 
> Daniel
> 
> >-----Original Message-----
> >From: foundry-nsp-bounces at puck.nether.net
> >[mailto:foundry-nsp-bounces at puck.nether.net] On Behalf Of Gunther 
> >Stammwitz
> >Sent: woensdag 4 oktober 2006 18:17
> >To: foundry-nsp at puck.nether.net
> >Subject: [f-nsp] Limitation in number of bgp-communities leads to 
> >closure ofbgp-session - possible bug?
> >
> >Hello colleages,
> >
> >I'm running software version 07.8.01dT53 on some jet core 
> and iron core 
> >modules and it looks like there is a problem with the bgp-code. The 
> >number of allowed bgp-communities one can is limited to 6 or 
> something.
> >
> >When one receives routes from neighbors with more than six 
> communities 
> >attached the bgp-sessions get closed. The reported error is:
> >Peer x.x.x.x
> >DOWN (Attribute Flags Error)
> >
> >show ip bgp nei x.x.x.x
> >1   IP Address: x.x.x.x, AS: 12345 (IBGP), RouterID: x.x.x.x
> >       Description: CORE1-Loopback
> >    State: OPEN_SENT, Time: 0h0m40s, KeepAliveTime: 20, HoldTime: 60
> >       Multihop-EBGP: yes, ttl: 1
> >       UpdateSource: Loopback 1
> >       SendCommunity: yes
> >       NextHopSelf: yes
> >       MaximumPrefixLimit: 230000
> >       SoftInboundReconfiguration: yes
> >       RefreshCapability: Received
> >    Messages:    Open    Update  KeepAlive Notification Refresh-Req
> >       Sent    : 74      2655695 6346      52           0          
> >       Received: 34      4290929 11825     2            0          
> >    Last Connection Reset Reason:Attribute Flags Error
> >    Notification Sent:     Finite State Machine Error
> >    Notification Received: Update Message Error/Attribute 
> Length Error
> >    Neighbor NLRI Negotiation:
> >      Peer Negotiated unicast capability
> >    TCP Connection state: ESTABLISHED
> >       Byte Sent:   45, Received: 64
> >       Local host:  x.x.x.2, Local  Port: 8026
> >       Remote host: x.x.x.1, Remote Port: 179
> >       ISentSeq: 3314228131  SendNext: 3314228177  TotUnAck: 
>          0
> >       TotSent:          46  ReTrans:           0  UnAckSeq: 
> 3314228177
> >       IRcvSeq:  1697078447  RcvNext:  1697078512  SendWnd:  
>      65000
> >       TotalRcv:         65  DupliRcv:          0  RcvWnd:   
>      16384
> >       SendQue:           0  RcvQue:            0  CngstWnd: 
>       3971
> >
> >
> >Example of "evil" prefix:
> >1       Prefix: 8.9.36.0/24,  Status: BE,  Age: 7d6h43m23s
> >         NEXT_HOP: x.x.x.x,  Learned from Peer: x.x.x.x (34088)
> >          LOCAL_PREF: 230,  MED: none,  ORIGIN: igp,  Weight: 0
> >           AS_PATH: 34088 3356 20473
> >            COMMUNITIES: 3356:3 3356:100 3356:123 3356:575 3356:2001
> >34088:44049 34088:44103 34088:46062 21501:40202 
> >            Adj_RIB_out count: 4,  Admin distance 20
> >
> >
> >As one can see there are nine communities attached to this route.
> >
> >To me this looks like a serious bug since one could spread a 
> route with 
> >a lot of communities throughout the internet and - if the 
> communities 
> >don't get overwritten by the transit-isps - could cause a reset of 
> >bgp-sessions to foundry routers.
> >
> >
> >Can anyone CONFIRM this behavior or is my problem located somewhere 
> >else?
> >
> >Gunther
> >
> >_______________________________________________
> >foundry-nsp mailing list
> >foundry-nsp at puck.nether.net
> >http://puck.nether.net/mailman/listinfo/foundry-nsp
> >
> >
> 
>