问题虽然在交换机重启后解决了，但是不明白问题原因，我用超级终端访问，显示的信息如下：
-Process= "L3MD_STAT", ipl= 0, pid= 32
-Traceback= 1B9F24 1BBEEC 1BC8E4 1CA444 1CA4F0 2D2FA4 2D4CB0 2D4D94 68CF2C 68D480 1DB024
24w0d: %SYS-2-MALLOCFAIL: Memory allocation of 140 bytes failed from 0x1BC8E0, alignment 0
Pool: Processor Free: 3761892 Cause: Memory fragmentation
Alternate Pool: None Free: 0 Cause: No Alternate pool
（给某一个进程分配内存的时候出错，可用内存池为0）
-Process= "L3MD_STAT", ipl= 0, pid= 32
-Traceback= 1B9F24 1BBEEC 1BC8E4 1CA444 1CA4F0 2D2FA4 2D4CB0 2D4D94 68CF2C 68D480 1DB024
%% Low on memory; try again later

Local Memory Statistics
Free = 3761892 Total = 54195772 Used = 50433880

%% Low on memory; try again later
......
其他的基本一样，有哪位高手能帮偶解读一下，是什么原因造成内存不足？先谢谢了

是不是受到了内存溢出攻击？

什么软件版本,能不能在出现故障的时候报tech信息抓下
从信息中可以看到提示原因是内存碎片,可以试着抓取下以下信息
show memory allocating-process totals
show memory summary
show logging

show memory allocating-process totals
Head Total( Used( Free( Lowest( Largest(
Processor C4E1C4 54195772 4951452 49244320 49083492 49096624
I/O 80000000 8388608 1209520 7179088 7132408 7131592

Allocator PC Summary for: Processor
..太长了，这个要么？

有没有试过将一部分端口shut down看看

Version 12.1(19)EA1
show logging
yslog logging: enabled (0 messages dropped, 4 messages rate-limited, 0 flushes, 0 overruns)
Console logging: level debugging, 42 messages logged
Monitor logging: level debugging, 0 messages logged
Buffer logging: level debugging, 46 messages logged
Exception Logging: size (4096 bytes)
File logging: disabled
Trap logging: level informational, 50 message lines logged
Logging to 192.168.0.55, 50 message lines logged

Log Buffer (4096 bytes):
5-EXTENDED_SYSID: Extended SysId enabled for type vlan
00:00:35: %SYS-5-CONFIG_I: Configured from memory by console
00:00:36: %SYS-5-RESTART: System restarted --
Cisco Internetwork Operating System Software
IOS ™ C3550 Software (C3550-I5Q3L2-M), Version 12.1(19)EA1, RELEASE SOFTWARE (fc2)
Copyright © 1986-2003 by cisco Systems, Inc.
Compiled Thu 23-Oct-03 21:44 by yenanh
00:00:37: %LINK-5-CHANGED: Interface FastEthernet0/15, changed state to administratively down
00:00:38: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/15, changed state to down
00:00:39: %LINK-3-UPDOWN: Interface FastEthernet0/1, changed state to up
00:00:39: %LINK-3-UPDOWN: Interface FastEthernet0/2, changed state to up
00:00:39: %LINK-3-UPDOWN: Interface FastEthernet0/9, changed state to up
00:00:39: %LINK-3-UPDOWN: Interface FastEthernet0/10, changed state to up
...

没有办法做，我用超级终端做的时候已经提示，内存过低，根本无法登陆了

这是正常时的信息吗?

-Process= "L3MD_STAT", ipl= 0, pid= 32
-Traceback= 1B9F24 1BBEEC 1BC8E4 1CA444 1CA4F0 2D2FA4 2D4CB0 2D4D94 68CF2C 68D480 1DB024
24w0d: %SYS-2-MALLOCFAIL: Memory allocation of 140 bytes failed from 0x1BC8E0, alignment 0
Pool: Processor Free: 3762244 Cause: Memory fragmentation
Alternate Pool: None Free: 0 Cause: No Alternate pool
在控制台一直显示这个信息，估计是往外发syslog...

是的，我想能不能查出点什么

排除病毒原因了吗?

如果它受到病毒攻击，他们与它相连的备交换机也会有影响的，还有与它直接相连的防火墙，而这些都正常，所以也许能排除病毒原因，

正常时候的信息没用