BGP Configuration Guide for Cisco 8000 Series Routers, Cisco IOS XR Releases

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Monitor BGP memory statistics

Updated: February 28, 2026

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Overview

Describes BGP memory statistics monitoring and guides users through procedures for observing BGP memory utilization and trends.

The BGP memory statistics is a serviceability feature that:

  • periodically monitors memory usage by the BGP process every 60 seconds,

  • logs any memory changes exceeding 1% of the configured resource limit (rlimit), and

  • triggers syslog notifications at 85%, 90%, and 95% of the rlimit to alert administrators before critical memory exhaustion.

  • The show bgp memory history command is a diagnostic tool that displays memory usage trends and variations over time, allowing administrators to analyze historical memory consumption patterns.

  • Syslog notifications are automated alerts generated when memory usage reaches predefined thresholds, enabling proactive management of memory resources before critical limits are reached.

  • A serviceability feature is a functionality designed to maintain system health by providing monitoring, alerting, and diagnostic capabilities that support troubleshooting and capacity planning.

The show bgp memory history command displays detailed historical memory usage information, including total memory in megabytes, percent of rlimit used, memory differences between records, and counts of networks, paths, path elements, and attributes for the default VRF.

Monitor BGP Memory Statistics

This task instructs you to check the historical memory usage of the BGP process to monitor memory trends and manage resources proactively.

Procedure

1.

Use the show bgp memory history command on the active router to verify the BGP memory history:

Example:

Router# show bgp memory history 

History of memory changes recorded for a threshold greater than 1.0% of rlimit. 
Last shown record displays current values. 
Network information for default VRF. 

Time               Memory(MB)  Rlimit(%)  Memory diff(MB)  Networks  Paths     PathElems  Attributes 
Oct  2 16:30:37    152         1          152              400       400       400        9 
Oct  2 16:31:37    343         4          191              396952    396869    396952     725 
Oct  2 16:32:37    425         5          81               524567    513979    524567     8408 
Oct  2 16:42:38    741         9          316              1178605   1241533   1178604    10753 
Oct  2 16:43:38    985         12         243              1778234   1859254   1778234    11214 
Oct  2 19:42:39    901         11         -84              1800688   678607    1800688    10911 
Oct  2 19:45:39    766         9          -136             1332259   688784    1332259    10943

The show command output displays memory change history for thresholds above 1.0% of the resource limit, with the latest record reflecting current values on the active router. It includes network details for the default VRF such as timestamps, memory in MB, rlimit percentage, memory differences, and counts of networks, paths, path elements, and attributes.
2.

Use the show bgp memory history standby command on the standby router to verify the BGP memory history:

Example:

Router# show bgp memory history standby 
Sat Mar  2 00:26:46.874 UTC

History of memory changes recorded for a threshold greater than 1.0% of rlimit.
Last shown record displays current values.
Network information for default VRF.

Time               Memory(MB)  Rlimit(%)  Memory diff(MB)  Networks  Paths     PathElems  Attributes  
Feb  9 03:39:04    98          1          98               0         0         0          0           
Feb  9 03:42:04    2913        35         2814             2372674   14546789  2372674    170613      
Feb  9 03:43:04    3129        38         216              2466877   16016399  2466877    181072      
Feb  9 03:44:04    3310        40         180              2510788   17302274  2510788    190648      
Feb  9 03:45:04    3601        43         291              2579305   19470841  2579305    210759      
Feb  9 03:46:04    3825        46         224              2657361   20952659  2657361    240920      
Feb  9 03:47:04    4063        49         238              2747506   22538284  2747506    262756      
Feb  9 03:48:04    4298        52         234              2830363   24126386  2830363    284014      
Feb  9 03:49:04    4530        55         231              2909578   25734085  2909578    304881      
Feb  9 03:50:04    4753        58         222              2984782   27302279  2984782    324646      
Feb  9 03:51:04    4961        60         208              3057329   28792696  3057329    342571      
Feb  9 03:52:05    5177        63         215              3135909   30322183  3135909    360386      
Feb  9 03:53:05    5393        65         216              3223111   31851898  3223111    377234      
Feb  9 03:54:05    5550        67         156              3229253   33250926  3229253    382132      
Feb  9 03:55:05    5694        69         143              3229253   34599173  3229253    385339      
Feb  9 03:56:05    5832        71         138              3229253   35912290  3229253    387534      
Feb  9 03:57:05    5987        73         155              3229257   37416025  3229257    389403      
Feb  9 03:58:05    6133        74         145              3229257   38817868  3229257    390404      
Mar  2 00:26:46    6248        76         114              3229257   39991732  3229257    390551

The show command output displays memory change history for thresholds above 1.0% of the resource limit, with the latest record reflecting current values on the standby router. It includes network details for the default VRF such as timestamps, memory in MB, rlimit percentage, memory differences, and counts of networks, paths, path elements, and attributes.