My Cisco My F5-

6900分区结构

web@mycisco.cn (纳米) — Fri, 05 Jun 2009 11:55:57 +0800

[root@localhost:NO LICENSE] images # df
Filesystem 1K-blocks Used Available Use% Mounted on
/dev/sda5 3465292 116312 3172948 4% /
/dev/sda7 3465292 34124 3255136 2% /config
/dev/sda8 20791956 131956 19603808 1% /var
...

暴风影音DNS事件分析

web@mycisco.cn (纳米) — Mon, 25 May 2009 10:38:02 +0800

点此下载

分析此次与DNS事件瘫痪前因后果，暴风影音\dnspod为何处在事件风口浪尖

如何应对，F5的解决方案是什么。

F5 NAT ,SNAT上的连接空闲超时idletimeout是由谁控制

web@mycisco.cn (纳米) — Tue, 19 May 2009 10:08:13 +0800

F5上，对于NAT上的连接超时空闲时间 idletimeout 是由对应协议的profile来控制的，比如tcp默认300秒。the idle timeout for a connection through a BIG-IP NAT should be 300 seconds。

注意：对于NAT，一些payload部分还有ip地址的协议不太适合，比如ftp，dns等。同时NAT上的超时时间控制在某些协议上（

9.4.4, 9.4.3, 9.4.2...

SOL9786: The mcpd daemon may report an error message or crash when handling a large number of transactions

web@mycisco.cn (纳米) — Wed, 13 May 2009 13:43:31 +0800

This is the result of a known issue. The mcpd process uses the XtremeDB database when handling objects, which has a fixed transaction size of 5,000. When handling more than 5,000 transactions, the mcpd process may crash or report an error message in the /var/log/ltm file that appears similar to the following example:
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用CISCO的console server 路由器连接F5console口实现远程console口登录

web@mycisco.cn (纳米) — Tue, 12 May 2009 15:53:01 +0800

1.在CISCO路由器上配置反向telnet，连接好八爪鱼。

2.注意配置line中speed stopbits配置，speed 19200 ，stopbits 1. 其他按照标准配置即可

3.用CISCO的那种一头是DB9一头是水晶头的那种线连到F5 console口上

4.用网线扩展器和一个全反线把八爪鱼的头和F5 console口出来的那个水晶头连接起来即可

以后就可以远程到CISCO路由器上，然后telnet +ip +线路端口就可以连接了。

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F5上对某一连接的发送和接收是在不同VLAN上进行的情况处理 asymmetric connections across multiple VLANs

web@mycisco.cn (纳米) — Sun, 10 May 2009 23:10:14 +0800

缺省情况下，F5要求从F5发送出去的请求的响应必须在同一VLAN上被接收到，否则该连接将被RST掉，这是VLAN-key特性。如果一个连接请求和响应分别发生在不同VLAN上，那么必须关闭vlan-key功能。在system- general配置界面中有关于vlan-key的设置。

关闭vlan-key特性后，有以下副作用：

1. PVA功能将散失 SOL6417: PVA is not compatible with asymmetric connections across multiple VLANs

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绝密文件094235205059号

web@mycisco.cn (纳米) — Thu, 23 Apr 2009 20:50:59 +0800

请输入密码查看文章及评论. 成功输入密码后的120分钟内, 可以直接点击查看文章, 直到关闭浏览器.

SOL3605-udp-基于每包LB-packet by packet

web@mycisco.cn (纳米) — Fri, 17 Apr 2009 22:18:03 +0800

The BIG-IP system processes UDP packets sent from the same IP address and port as part of a connection. The BIG-IP system will send those packets to the same node as long as the connection lives.

In some instances, it is preferable to load balance UDP packets individually.

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LTM: Action on Service Down

web@mycisco.cn (纳米) — Fri, 17 Apr 2009 18:29:53 +0800

BIG-IP has long been known for its extensive application monitoring capabilities, and LTM has expanded both the types of monitoring activities possible and the possible reactions to varying monitor states. In this article, I'll explain the options for the "Action on Service Down" setting.
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DNS关于递归的一些学习记录[更新中]

web@mycisco.cn (纳米) — Sun, 12 Apr 2009 06:50:24 +0800

缺省配置情况下local DNS（BIND开启递归，如果关闭递归或关闭缓存呢？？待测试）在将请求进行递归时时携带的查询包是包含不期望其递归服务器进行再次递归的：

但是本机发送的DNS查询请求是期望local dns进行递归的：

从nslookup的debug信息也可以看出
> www.myf5.net
Server: [192.168.0.189]
Address: 192.168.0.189

------------
Got answer:
HEADER:
opcode = QUERY, id = 3, rcode = NOERROR
...