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Here's an example command and output from a 2921 running BGP:

router#show ip bgp summary
BGP router identifier a.b.c.d, local AS number xxxxx
BGP table version is 352841773, main routing table version 352841773
629306 network entries using 90620064 bytes of memory
629307 path entries using 50344560 bytes of memory
106106/105965 BGP path/bestpath attribute entries using 16976960 bytes of memory
97455 BGP AS-PATH entries using 4812166 bytes of memory
1 BGP ATTR_SET entries using 40 bytes of memory
12009 BGP community entries using 1523662 bytes of memory
116 BGP extended community entries using 7108 bytes of memory
220 BGP route-map cache entries using 7920 bytes of memory
0 BGP filter-list cache entries using 0 bytes of memory
BGP using 164292440 total bytes of memory
BGP activity 12705113/12039960 prefixes, 19056016/18390892 paths, scan interval 60 secs

Neighbor        V           AS MsgRcvd MsgSent   TblVer  InQ OutQ Up/Down  State/PfxRcd
a.b.c.d         4        xxxxx       0       0        1    0    0 8w4d     Idle (Admin)
a.b.c.d         4        xxxxx 7319210   47142 352841520    0    0 2w1d       629303
a.b.c.d         4        xxxxx   33222 4258052 352841520    0    0 2w6d            1
a.b.c.d         4        xxxxx   33251 4258051 352841520    0    0 2w6d            1

I'm curious about this line:

BGP activity 12705113/12039960 prefixes, 19056016/18390892 paths, scan interval 60 secs

What do the four bold numbers mean?

All I can find in the Cisco Command Reference is this:

BGP activity... Displays the number of times that memory has been allocated or released for a path or prefix.

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  • Did any answer help you? if so, you should accept the answer so that the question doesn't keep popping up forever, looking for an answer. Alternatively, you could provide and accept your own answer. – Ron Maupin Aug 7 '17 at 22:26
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What that is saying is that memory has been allocated to your prefixes 12705113 times and released 12039960 times. It has been allocated to your paths 19056016 and released 18390892

I suspect your router has been up for a while.

A route announcement is sometimes referred to as a 'prefix'. A prefix announced in BGP consists of the IPV4 or IPV6 address block being announced and also a path of AS numbers, indicating which ASNs the traffic must pass through to reach the announced address block. A BGP prefix would look something like (IPV4): 701 1239 42 206.24.14.0/24. The /24 part is referred to as a CIDR mask. The /24 indicates that the first 24 bits in the address block is the ?network? part of the address block.

https://www.sprint.net/index.php?p=faq_bgp

BGP Activity displays the number of times that memory has been allocated or released for a path or prefix.

http://www.cisco.com/c/en/us/td/docs/ios/iproute_bgp/command/reference/irg_book/irg_bgp5.html#wp1162687

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