Command
Logging Buffered
Use
This is a handy command that stores log messages so they can be reviewed later.
This is especially useful when you are telneting between multiple routers as you would normally miss the console or debug messages on the router your not connected to.
Each logging level also enables the logging level below it, so logging buffered 7 or logging buffered debug will enable all log messages.
Syntax
R1(config)#logging buffered <level>
Optional Switches
| <0-7> <4096-2147483647> alerts critical debugging emergencies errors filtered informational notifications warnings xml |
Logging severity level Logging buffer size Immediate action needed (severity=1) Critical conditions (severity=2) Debugging messages (severity=7) System is unusable (severity=0) Error conditions (severity=3) Enable filtered logging Informational messages (severity=6) Normal but significant conditions (severity=5) Warning conditions (severity=4) Enable logging in XML to XML logging buffer |
Example
In this example, we will enable logging buffered debug.
R2(config)#logging buffered debug
Now we will telnet from R1 to R2 and check the debug output.
R1(config)#do telnet 2.2.2.2 Trying 2.2.2.2 … Open User Access Verification Password: R2>en Password: R2#debug ip packet IP packet debugging is on R2#show log Syslog logging: enabled (11 messages dropped, 0 messages rate-limited, 0 flushes, 0 overruns, xml disabled, filtering disabled) Console logging: level debugging, 630 messages logged, xml disabled, filtering disabled Monitor logging: level debugging, 0 messages logged, xml disabled, filtering disabled Buffer logging: level debugging, 115 messages logged, xml disabled, filtering disabled Logging Exception size (4096 bytes) Count and timestamp logging messages: disabled No active filter modules. Trap logging: level informational, 30 message lines logged Log Buffer (4096 bytes): , len 41, rcvd 4 *Mar 1 02:45:01.667: IP: tableid=0, s=2.2.2.2 (local), d=10.1.1.1 (FastEthernet0/0), routed via FIB *Mar 1 02:45:01.671: IP: s=2.2.2.2 (local), d=10.1.1.1 (FastEthernet0/0), len 41, sending *Mar 1 02:45:01.767: IP: tableid=0, s=10.1.1.1 (FastEthernet0/0), d=2.2.2.2 (Loopback0), routed via RIB *Mar 1 02:45:01.771: IP: s=10.1.1.1 (FastEthernet0/0), d=2.2.2.2, len 41, rcvd 4 *Mar 1 02:45:01.791: IP: tableid=0, s=2.2.2.2 (local), d=10.1.1.1 (FastEthernet0/0), routed via FIB *Mar 1 02:45:01.795: IP: s=2.2.2.2 (local), d=10.1.1.1 (FastEthernet0/0), len 41, sending *Mar 1 02:45:01.871: IP: tableid=0, s=10.1.1.1 (FastEthernet0/0), d=2.2.2.2 (Loopback0), routed via RIB *Mar 1 02:45:01.875: IP: s=10.1.1.1 (FastEthernet0/0), d=2.2.2.2, len 41, rcvd 4 *Mar 1 02:45:01.875: IP: tableid=0, s=2.2.2.2 (local), d=10.1.1.1 (FastEthernet0/0), routed via FIB *Mar 1 02:45:01.875: IP: s=2.2.2.2 (local), d=10.1.1.1 (FastEthernet0/0), len 41, sending P: s=2.2.2.2 (local), d=10.1.1.1 (FastEthernet0/0), len 546, sending *Mar 1 02:45:06.619: IP: tableid=0, s=10.1.1.1 (FastEthernet0/0), d=2.2.2.2 (Loopback0), routed via RIB *Mar 1 02:45:06.619: IP: s=10.1.1.1 (FastEthernet0/0), d=2.2.2.2, len 40, rcvd 4 *Mar 1 02:45:06.811: IP: tableid=0, s=10.1.1.1 (FastEthernet0/0), d=2.2.2.2 (Loopback0), routed via RIB), len 41, sending *Mar 1 02:45:02.175: IP: tableid=0, s=10.1.1.1 (FastEthernet0/0), d=2.2.2.2 (Loopback0), routed via RIB *Mar 1 02:45:02.175: IP: s=10.1.1.1 (FastEthernet0/0), d=2.2.2.2, len 40, rcvd 4 *Mar 1 02:45:02.283: IP: tableid=0, s=10.1.1.1 (FastEthernet0/0), d=2.2.2.2 (Loopback0), routed via RIB *Mar 1 02:45:02.287: IP: s=10.1.1.1 (FastEthernet0/0), d=2.2.2.2, len 41, rcvd 4 *Mar 1 02:45:02.295: IP: tableid=0, s=2.2.2.2 (local), d=10.1.1.1 (FastEthernet0/0), routed via FIB *Mar 1 02:45:02.299: IP: s=2.2.2.2 (local), d=10.1.1.1 (FastEthernet0/0), len 41, sending *Mar 1 02:45:02.491: IP: tableid=0, s=10.1.1.1 (FastEthernet0/0), d=2.2.2.2 (Loopback0), routed via RIB *Mar 1 02:45:02.495: IP: s=10.1.1.1 (FastEthernet0/0), d=2.2.2.2, len 41, rcvd 4 *Mar 1 02:45:02.503: IP: tableid=0, s=2.2.2.2 (local), d=10.1.1.1 (FastEthernet0/0), routed via FIB *Mar 1 02:45:02.507: IP: s=2.2.2.2 (local), d=10.1.1.1 (FastEthernet0/0), len 41, sending *Mar 1 02:45:02.567: IP: s=2.2.2.2 (local), d=224.0.0.9 (Loopback0), len 132, sending broad/multicast *Mar 1 02:45:02.571: IP: s=2.2.2.2 (Loopback0), d=224.0.0.9, len 132, rcvd 2 *Mar 1 02:45:02.735: IP: tableid=0, s=10.1.1.1 (FastEthernet0/0), d=2.2.2.2 (Loopback0), routed via RIB *Mar 1 02:45:02.739: IP: s=10.1.1.1 (FastEthernet0/0), d=2.2.2.2, len 40, rcvd 4 *Mar 1 02:45:02.855: IP: tableid=0, s=10.1.1.1 (FastEthernet0/0), d=2.2.2.2 (Loopback0), routed via RIB *Mar 1 02:45:02.859: IP: s=10.1.1.1 (FastEthernet0/0), d=2.2.2.2, len 41, rcvd 4 *Mar 1 02:45:02.867: IP: tableid=0, s=2.2.2.2 (local), d=10.1.1.1 (FastEthernet0/0), routed via FIB *Mar 1 02:45:02.871: IP: s=2.2.2.2 (local), d=10.1.1.1 (FastEthernet0/0), len 41, sending *Mar 1 02:45:03.075: IP: tableid=0, s=10.1.1.1 (FastEthernet0/0), d=2.2.2.2 (Loopback0), routed via RIB *Mar 1 02:45:03.079: IP: s=10.1.1.1 (FastEthernet0/0), d=2.2.2.2, len 40, rcvd 4 Mar 1 02:45:07.703: IP: s=2.2.2.2 (local), d=10.1.1.1 (FastEthernet0/0), len 142, sending 1 02:45:04.823: IP: s=10.1.1.2 (local), d=224.0.0.10 (FastEthernet0/0), len 60, sending broad/multicast *Mar 1 02:45:05.919: IP: tableid=0, s=10.1.1.1 (FastEthernet0/0), d=2.2.2.2 (Loopback0), routed via RIB *Mar 1 02:45:05.923: IP: s=10.1.1.1 (FastEthernet0/0), d=2.2.2.2, len 42, rcvd 4 *Mar 1 02:45:05.931: IP: tableid=0, s=2.2.2.2 (local), d=10.1.1.1 (FastEthernet0/0), routed via FIB *Mar 1 02:45:05.935: IP: s=2.2.2.2 (local), d=10.1.1.1 (FastEthernet0/0), len 42, sending *Mar 1 02:45:06.019: IP: tableid=0, s=2.2.2.2 (local), d=10.1.1.1 (FastEthernet0/0), routed via FIB *Mar 1 02:45:06.023: IP: s=2.2.2.2 (local), d=10.1.1.1 (FastEthernet0/0), len 576, sending *Mar 1 02:45:06.079: IP: tableid=0, s=10.1.1.1 (FastEthernet0/0), d=2.2.2.2 (Loopback0), routed via RIB