0x4E-etwork
Single DHCP server for multiple VLANs
During lunch, a friend of mine ask me about how does one go about setting up 1 DHCP server to serve multiple VLANs.
Generally the step listed below, involves router-on-a-stick method
1. Create VLANs on the router
2. Assign IP addresses to the each VLAN on the router.
3. Configure the router port connected to the switch as a VLAN trunk port.
4. Define routes to each network.
5. Configure the router to relay DHCP requests.
6. Create the VLANs on the switch.
7. Configure the switch port connected to the router as a VLAN trunk.
8. Add switch access ports to the appropriate VLANs.
Technorati Tags: DHCP, VLAN, Router-On-A-Stick
Read Full Post | Make a Comment ( None so far )Grep MAC address from under Linux
Linux command to grep out the MAC address
linuxhost# ifconfig -a eth0 | grep ‘HWaddr’
eth0 Link encap:Ethernet HWaddr 00:14:C2:5C:99:F1
Technorati Tags: Linux, MAC address
Read Full Post | Make a Comment ( None so far )MPLS FAQ For Beginners
Embarking on my personal journey into the topic of MPLS, I stumble upon this Cisco site which contain some common question that would be asked by a non MPLS user. “MPLS FAQ For Beginners” [LINK]
Technorati Tags: MPLS, Cisco, Network
Read Full Post | Make a Comment ( None so far )Procedure to reset password on Cisco Catalyst 3550
- On a 3550 release the mode button after the 1x port LED goes out.
- flash_init
- load_helper
- dir flash:
- rename flash:config.text flash:config.backup
- boot
- rename flash:config.backup config.text
- copy flash:config.text system:running-config
- config terminal
- no enable secret
- enable password password
- copy running-config startup-config
Technorati Tags: reset password, catalyst 3550
Read Full Post | Make a Comment ( None so far )Configuration files for Hearbeat ( Linux-HA )
Technorati Tags: linux, heartbeat, high availability, clustering
Read Full Post | Make a Comment ( None so far )Set password on Cisco Catalyst 6509
c6509>enable
c6509>(enable)set passsword
Enter old password:
Enter new password:
Retype new password:
Password changed.
Technorati Tags: Cisco, Catalyst, 6509, Set
Read Full Post | Make a Comment ( None so far )Stop Cisco console message from interrupting commands
r1(config)#line console 0
r1(config-line)#logging synchronous
r1(config-line)#^Z
r1#
*Mar 1 00:22:21.479: %SYS-5-CONFIG_I: Configured from console by console
Technorati Tags: Cisco, router, console, logging
Read Full Post | Make a Comment ( None so far )Clear Cisco router configuration
router1#write erase
Erasing the nvram filesystem will remove all configuration files! Continue? [confirm]
[OK]
Erase of nvram: complete
router1#
*Mar 1 00:09:12.679: %SYS-7-NV_BLOCK_INIT: Initialized the geometry of nvram
* Do a “reload” to ensure the startup-config and running-config are cleared.
router1#reload
System configuration has been modified. Save? [yes/no]: no
Proceed with reload? [confirm]y
*Mar 1 00:17:55.435: %SYS-5-RELOAD: Reload requested by console. Reload Reason: Reload Command.
Technorati Tags: Cisco, Router, Configuration
Read Full Post | Make a Comment ( None so far )Address Allocation for Private Internets
IP address space for private networks have been reserved according to RFC 1918
• 10.0.0.0–10.255.255.255—Single Class A network numbers
• 172.16.0.0–172.31.255.255—Contiguous Class B network numbers
• 192.168.0.0–192.168.255.255—Contiguous Class C network numbers
Technorati Tags: Private IP Address, IP, APIPA, RFC 1918, Network
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