[c-nsp] Why only 10 has buckets?
Paul
paul at gtcomm.net
Sat May 16 21:45:18 EDT 2015
There are 16 buckets on the sup720, i am not positive about the sup2t.
If you were to go over 16 paths it would cut them in half (like using 10
buckets for 20 paths) because that's how it has to assign it in the
hardware.
The hardware is limited to using (i believe) a maximum of 16 paths per
prefix 'route' so anything over 16 would be pointless.
I think some of the newer hardware has been changed to 32 or 64 but as
far as I know the s720 and most likely the s2t is limited to 16 (and it
is i just edited my email lol)
Browsing a sup2t white paper while typing this out.. I see:
Load sharing at the FIB levels occurs when a single prefix possesses
multiple adjacencies. This is usually achieved by using multiple equal
cost paths to the destination. This situation is highly desirable for
redundancy purposes. The Supervisor 2T is capable of load-balancing
traffic for up to 16 paths for each single prefix (IPv4 or IPv6). Load
balancing is performed on a per-flow basis and the following
configuration can be used to program the load-balancing hash:
So I suppose the new question is, why when using more than 16 paths does
it cut it in half instead of using the first 16 and using the remaining
as backups in case one of the 16 are deleted..
My suggestion would be to use 16 and no more per destination prefix
On 5/15/2015 6:02 PM, Peter Kranz wrote:
> C6506-E running Sup2T.. I was under the impression there were more than 10
> hash buckets available? I can't seem to generate anycast load balancing over
> 10 destinations.. Here is an example with 20 paths where CEF only inserts
> 10..
>
>
>
> rtr-sungard#sho ip cef 208.76.31.254 internal
>
> 208.76.31.254/32, epoch 8, flags rib only nolabel, rib defined all labels,
> RIB[B], refcount 6, per-destination sharing
>
> sources: RIB, Adj
>
> feature space:
>
> Broker: linked
>
> NetFlow: Origin AS 65009, Peer AS 0, Mask Bits 0
>
> IPRM: 0x00018000
>
> subblocks:
>
> Adj source: IP adj out of Vlan10, addr 208.76.31.254 2C4D49E0
>
> Dependent covered prefix type adjfib cover 208.76.31.0/24
>
> ifnums:
>
> Vlan10(20): 162.244.60.50, 162.244.60.51, 162.244.60.52, 162.244.60.53
>
> 162.244.60.54, 162.244.60.55, 162.244.60.56, 162.244.60.57
>
> 162.244.60.58, 162.244.60.59, 162.244.60.60, 162.244.60.61
>
> 162.244.60.62, 162.244.60.63, 162.244.60.64, 162.244.60.65
>
> 162.244.60.66, 162.244.60.67, 162.244.60.68, 162.244.60.69
>
> path 675395F4, path list 27D7F6F8, share 1/1, type recursive nexthop, for
> IPv4, flags resolved
>
> recursive via 162.244.60.50[IPv4:Default], fib 6C189DF4, 1 terminal fib
>
> path 6753A644, path list 27D808D8, share 1/1, type adjacency prefix, for
> IPv4
>
> attached to Vlan10, adjacency IP adj out of Vlan10, addr 162.244.60.50
> 2C4D5880
>
> path 67539A7C, path list 27D7F6F8, share 1/1, type recursive nexthop, for
> IPv4, flags resolved
>
> recursive via 162.244.60.51[IPv4:Default], fib 6C184B44, 1 terminal fib
>
> path 67539254, path list 27D80390, share 1/1, type adjacency prefix, for
> IPv4
>
> attached to Vlan10, adjacency IP adj out of Vlan10, addr 162.244.60.51
> 2C4D5A20
>
> path 675398AC, path list 27D7F6F8, share 1/1, type recursive nexthop, for
> IPv4, flags resolved
>
> recursive via 162.244.60.52[IPv4:Default], fib 5C1EC38C, 1 terminal fib
>
> path 6753B280, path list 27D807A0, share 1/1, type adjacency prefix, for
> IPv4
>
> attached to Vlan10, adjacency IP adj out of Vlan10, addr 162.244.60.52
> 2C4D5BC0
>
> path 67539F04, path list 27D7F6F8, share 1/1, type recursive nexthop, for
> IPv4, flags resolved
>
> recursive via 162.244.60.53[IPv4:Default], fib 5C1EC23C, 1 terminal fib
>
> path 6753A400, path list 27D809A8, share 1/1, type adjacency prefix, for
> IPv4
>
> attached to Vlan10, adjacency IP adj out of Vlan10, addr 162.244.60.53
> 2C4D5D60
>
> path 67538C70, path list 27D7F6F8, share 1/1, type recursive nexthop, for
> IPv4, flags resolved
>
> recursive via 162.244.60.54[IPv4:Default], fib 2B7C0DCC, 1 terminal fib
>
> path 6753A970, path list 27D80B48, share 1/1, type adjacency prefix, for
> IPv4
>
> attached to Vlan10, adjacency IP adj out of Vlan10, addr 162.244.60.54
> 2C4D5F00
>
> path 675391E0, path list 27D7F6F8, share 1/1, type recursive nexthop, for
> IPv4, flags resolved
>
> recursive via 162.244.60.55[IPv4:Default], fib 2AD09878, 1 terminal fib
>
> path 6753A888, path list 27D80D50, share 1/1, type adjacency prefix, for
> IPv4
>
> attached to Vlan10, adjacency IP adj out of Vlan10, addr 162.244.60.55
> 2C4D60A0
>
> path 675397C4, path list 27D7F6F8, share 1/1, type recursive nexthop, for
> IPv4, flags resolved
>
> recursive via 162.244.60.56[IPv4:Default], fib 5F228B64, 1 terminal fib
>
> path 6753A1BC, path list 27D80EF0, share 1/1, type adjacency prefix, for
> IPv4
>
> attached to Vlan10, adjacency IP adj out of Vlan10, addr 162.244.60.56
> 2C4D6240
>
> path 67539B64, path list 27D7F6F8, share 1/1, type recursive nexthop, for
> IPv4, flags resolved
>
> recursive via 162.244.60.57[IPv4:Default], fib 1D623CC8, 1 terminal fib
>
> path 6753A4E8, path list 27D80C18, share 1/1, type adjacency prefix, for
> IPv4
>
> attached to Vlan10, adjacency IP adj out of Vlan10, addr 162.244.60.57
> 2C4D63E0
>
> path 6753A318, path list 27D7F6F8, share 1/1, type recursive nexthop, for
> IPv4, flags resolved
>
> recursive via 162.244.60.58[IPv4:Default], fib 5837CE50, 1 terminal fib
>
> path 6753AA58, path list 27D80AE0, share 1/1, type adjacency prefix, for
> IPv4
>
> attached to Vlan10, adjacency IP adj out of Vlan10, addr 162.244.60.58
> 2C4D7420
>
> path 6753933C, path list 27D7F6F8, share 1/1, type recursive nexthop, for
> IPv4, flags resolved
>
> recursive via 162.244.60.59[IPv4:Default], fib 1BD00500, 1 terminal fib
>
> path 6753AD84, path list 27D80600, share 1/1, type adjacency prefix, for
> IPv4
>
> attached to Vlan10, adjacency IP adj out of Vlan10, addr 162.244.60.59
> 2C4D6580
>
> path 675390F8, path list 27D7F6F8, share 1/1, type recursive nexthop, for
> IPv4, flags resolved
>
> recursive via 162.244.60.60[IPv4:Default], fib 243196A4, 1 terminal fib
>
> path 53BC20CC, path list 14C36BD0, share 1/1, type adjacency prefix, for
> IPv4
>
> attached to Vlan10, adjacency IP adj out of Vlan10, addr 162.244.60.60
> 2C4D6720
>
> path 6753AD10, path list 27D7F6F8, share 1/1, type recursive nexthop, for
> IPv4, flags resolved
>
> recursive via 162.244.60.61[IPv4:Default], fib 6C187A84, 1 terminal fib
>
> path 67539CC0, path list 27D80DB8, share 1/1, type adjacency prefix, for
> IPv4
>
> attached to Vlan10, adjacency IP adj out of Vlan10, addr 162.244.60.61
> 2C4D56E0
>
> path 6753A230, path list 27D7F6F8, share 1/1, type recursive nexthop, for
> IPv4, flags resolved
>
> recursive via 162.244.60.62[IPv4:Default], fib 5D3616C8, 1 terminal fib
>
> path 6753AB40, path list 27D80CE8, share 1/1, type adjacency prefix, for
> IPv4
>
> attached to Vlan10, adjacency IP adj out of Vlan10, addr 162.244.60.62
> 2C4D5540
>
> path 6753A2A4, path list 27D7F6F8, share 1/1, type recursive nexthop, for
> IPv4, flags resolved
>
> recursive via 162.244.60.63[IPv4:Default], fib 6306FA24, 1 terminal fib
>
> path 6753A55C, path list 27D80A10, share 1/1, type adjacency prefix, for
> IPv4
>
> attached to Vlan10, adjacency IP adj out of Vlan10, addr 162.244.60.63
> 2C4D53A0
>
> path 67539FEC, path list 27D7F6F8, share 1/1, type recursive nexthop, for
> IPv4, flags resolved
>
> recursive via 162.244.60.64[IPv4:Default], fib 1F8877F0, 1 terminal fib
>
> path 6753ADF8, path list 27D80940, share 1/1, type adjacency prefix, for
> IPv4
>
> attached to Vlan10, adjacency IP adj out of Vlan10, addr 162.244.60.64
> 2C4D5200
>
> path 6753B4C4, path list 27D7F6F8, share 1/1, type recursive nexthop, for
> IPv4, flags resolved
>
> recursive via 162.244.60.65[IPv4:Default], fib 58D55638, 1 terminal fib
>
> path 6753A9E4, path list 27D80668, share 1/1, type adjacency prefix, for
> IPv4
>
> attached to Vlan10, adjacency IP adj out of Vlan10, addr 162.244.60.65
> 2C4D5060
>
> path 6753B9C0, path list 27D7F6F8, share 1/1, type recursive nexthop, for
> IPv4, flags resolved
>
> recursive via 162.244.60.66[IPv4:Default], fib 5D3694C8, 1 terminal fib
>
> path 6753A6B8, path list 27D80FC0, share 1/1, type adjacency prefix, for
> IPv4
>
> attached to Vlan10, adjacency IP adj out of Vlan10, addr 162.244.60.66
> 2C4D4EC0
>
> path 28011AAC, path list 27D7F6F8, share 1/1, type recursive nexthop, for
> IPv4, flags resolved
>
> recursive via 162.244.60.67[IPv4:Default], fib 1DFD3BD8, 1 terminal fib
>
> path 6753B694, path list 27D80188, share 1/1, type adjacency prefix, for
> IPv4
>
> attached to Vlan10, adjacency IP adj out of Vlan10, addr 162.244.60.67
> 2C4D4D20
>
> path 28010DFC, path list 27D7F6F8, share 1/1, type recursive nexthop, for
> IPv4, flags resolved
>
> recursive via 162.244.60.68[IPv4:Default], fib 6C18A1E4, 1 terminal fib
>
> path 675393B0, path list 27D80120, share 1/1, type adjacency prefix, for
> IPv4
>
> attached to Vlan10, adjacency IP adj out of Vlan10, addr 162.244.60.68
> 2C4D4B80
>
> path 28011B20, path list 27D7F6F8, share 1/1, type recursive nexthop, for
> IPv4, flags resolved
>
> recursive via 162.244.60.69[IPv4:Default], fib 22BAB6E8, 1 terminal fib
>
> path 67539920, path list 27D80E20, share 1/1, type adjacency prefix, for
> IPv4
>
> attached to Vlan10, adjacency IP adj out of Vlan10, addr 162.244.60.69
> 2C4D4840
>
> output chain:
>
> loadinfo 53BB6B24, per-session, 10 choices, flags 0003, 5 locks
>
> flags: Per-session, for-rx-IPv4
>
> 10 hash buckets
>
> < 0 > IP adj out of Vlan10, addr 162.244.60.50 2C4D5880
>
> < 1 > IP adj out of Vlan10, addr 162.244.60.51 2C4D5A20
>
> < 2 > IP adj out of Vlan10, addr 162.244.60.52 2C4D5BC0
>
> < 3 > IP adj out of Vlan10, addr 162.244.60.53 2C4D5D60
>
> < 4 > IP adj out of Vlan10, addr 162.244.60.54 2C4D5F00
>
> < 5 > IP adj out of Vlan10, addr 162.244.60.55 2C4D60A0
>
> < 6 > IP adj out of Vlan10, addr 162.244.60.56 2C4D6240
>
> < 7 > IP adj out of Vlan10, addr 162.244.60.57 2C4D63E0
>
> < 8 > IP adj out of Vlan10, addr 162.244.60.58 2C4D7420
>
> < 9 > IP adj out of Vlan10, addr 162.244.60.59 2C4D6580
>
> Subblocks:
>
> None
>
>
>
> Peter Kranz
> www.UnwiredLtd.com <http://www.unwiredltd.com/>
> Desk: 510-868-1614 x100
> Mobile: 510-207-0000
> pkranz at unwiredltd.com <mailto:pkranz at unwiredltd.com>
>
>
>
> _______________________________________________
> cisco-nsp mailing list cisco-nsp at puck.nether.net
> https://puck.nether.net/mailman/listinfo/cisco-nsp
> archive at http://puck.nether.net/pipermail/cisco-nsp/
>
--
GloboTech Communications
Phone: 1-514-907-0050 x 215
Toll Free: 1-(888)-GTCOMM1
Fax: 1-(514)-907-0750
paul at gtcomm.net
http://www.gtcomm.net
More information about the cisco-nsp
mailing list