C2960 config - What do the commands do

Hi, however its reasonably to see official cisco IOS definition of these commands I try to write some notes from my head and cco.

switch off pad protocol on the router.

Packet Assembly and Disassembly (PAD) is used for sending and receiving "raw" data over IP networks. The modem takes care of establishing IP network connections, as well as the encapsulation of data within UDP or TCP packets. This eliminates the need for a TCP/IP stack running on the host device.

switch on the service of timestamping each debug log (when you type any debug command) the router produces. But in opposed to "datetime" you use "uptime".

The same what above, but applied to regular log data.

switch on cisco algorithm to hide clear text password (enable, telnet etc) and instead show this password as a meaningless string (ggtrg9543ygtrhth). In opposed to hash algorithm (e.g. MD5) its eassy to decipher this string to original password.

To enable visible sequence numbering of system logging messages, use the service sequence-numbers command in global configuration mode. Each system status messages logged in the system logging process have a sequence reference number applied. This command makes that number visible by displaying it with the message. The sequence number is displayed as the first part of the system status message.

For example:

000066: .Mar 22 15:35:57 PST: %SYS-5-CONFIG_I: Configured from console by console

You do not going to use AAA model (authentication, authorization and accounting).

You set UTC time zone. UTC is Coordinated Universal Time. "1" after UTC means one hour shift, i.e. this is UTC+1=CET (and some others, BST, IST, WEST) CET is Central European Time.

Configure the system to automatically switch to summer time (daylight saving time).

You want to save and use the first subent (subnet zero). This sybnet has the same network address what main network (the subnetted one) but longer subnet mask For example:

10.0.0.0/8 is main network 10.0.0.0/24 is subnet zero of this network. With the commands "no ip subnet-zero" You are not allowed to use this subnet. Then You can use 10.0.1.0/24 subnet as the first usable subnet.

switch off automatic verification of cisco files. When You copy some files to your router its safe to verify theirs control sum. For example:

copy /verify tftp://10.1.1.1/jdoe/c7200-js-mz disk0: verify disk0:c7200-js-mz reload /verify

With this feature switch on You do not need to do this, insted router do this automatically.

You want to run pvst (per-Vlan spannig tree) mode od spanning tree protocol. It means that in every vlan throughout your switched network seperate instance of STP frames will be running. Its good only for small number of vlans. In other cases its safe to use MST (multiple spanning tree)

Enable the extended system ID feature on a chassis that supports 1024 MAC addresses.Releases 12.1(13)E and later support chassis with 64 or 1024 MAC addresses. For chassis with 64 MAC addresses, STP uses the extended system ID plus a MAC address to make the bridge ID unique for each VLAN.

It configures the Internal Vlan allocation policy. You can choose between "ascending" and "descending". Enter the ascending keyword to allocate internal VLANs from 1006 and up. Enter the descending keyword to allocate internal VLAN from 4094 and down.

1006-4094 - this is extended range of etherenet-only vlans, they are not propagated by vtp protocol.

switch on control plane policing. The Control Plane Policing feature allows users to configure a quality of service (QoS) filter that manages the traffic flow of control plane packets to protect the control plane of Cisco IOS routers and switches against reconnaissance and denial-of-service (DoS) attacks. In this way, the control plane (CP) can help maintain packet forwarding and protocol states despite an attack or heavy traffic load on the router or switch.

*** More about these you can find on cisco.com in public area without CCO access.

Regards, Wlodek.

Great :-) Thank you Wlodek

Best Regards Martin