The embedded DHCP server on AOS 7 and AOS 8 is a less known feature. But it’s pretty handy in some cases, e.g. if you have no servers on premises, or you don’t want that a a non redundant firewall or router acts as DHCP server. Because you can run two or more switches as a virtual chassis, you can easily make the DHCP server role highly available.
The configuration is pretty easy.
Manually assigning ports to VLANs can be a time consuming and error prone process. Depending on the size of the network, there is a point where it doesn’t make sense to do this manually. Especially in SMB networks, VLANs are assigned manually, because the effort of automating the VLAN assignment exceeds the effort for manually assigning VLANs. Those environments are often very static. I know many SMB networks where VLAN have not been addressed for a long time. With declining costs for Layer 3 switches, the separation of workloads in VLANs for SMB customers became affordable. Server virtualization was another mainspring for VLANs and inter-VLAN routing. To be honest: I’m talking about SMB customers, not enterprise customers or enterprise-grade SMB customers (latter is my special term for SMB customers with enormous IT budgets…). But the main driver for VLANs was Voice over IP (VoIP). With the increasing proliferation of VoIP, even the smallest SMB customer were forced to use VLANs. But this led to situations, where customers had to change the switch config every time a new client or IP phone was added to the network. Common workarounds:
Today I saw an interesting behaviour of two Alcatel-Lucent Enterprise OmniSwitch 6450. Both switches has been configured as a stack, but one of the switches showed a flashing ID after the startup, and the stack was not formed. While I checked the logs and the status of the stack, I noticed that the slot number was incorrect. Furthermore the status showed “INC-LIC”.
-> show stack topology
Link A Link A Link B Link B
NI Role State Saved Link A Remote Remote Link B Remote Remote
Slot State NI Port State NI Port
----+-----------+--------+------+-------+-------+-------+-------+-------+-------
1 PRIMARY RUNNING 1 UP 1001 StackB DOWN 0 0
1001 PASS-THRU INC-LIC 2 DOWN 0 0 UP 1 StackA
-> show log swlog
<snip>
THU MAR 03 13:07:29 2016 STACK-MANAGER info == SM == Stack Port A Status Changed: DOWN
THU MAR 03 13:07:29 2016 STACK-MANAGER info == SM == NI 0 down notification sent to LAG
THU MAR 03 13:08:41 2016 STACK-MANAGER info == SM == Stack Port A Status Changed: UP
THU MAR 03 13:08:41 2016 STACK-MANAGER info == SM == Stack Port A MAC Frames TX/RX Enabled
THU MAR 03 13:08:42 2016 STACK-MANAGER info Retaining Module Id for slot 2 unit 0 as 1
THU MAR 03 13:08:46 2016 STACK-MANAGER info == SM == An element enters passthru mode (incompatible license)
<snip>
According to the stack status and the switch logs, there seems to be a problem with the licenses. So I checked the installed licenses on both switches. On switch showed Metro license:
Disclaimer: Thanks to ALE Deutschland GmbH, the german subsidiary of Alcatel-Lucent Enterprise, for loaning me two OmniSwitch 6450 switches.
I’m quite sure that you know Alcatel-Lucent, a leading vendor for telecommunication and networking equipment. But do you know Alcatel-Lucent Enterprise (ALE)? In April 2015, Nokia placed an offer to buy Alcatel-Lucent for ~ 15 billion euro. Six months before, in October 2014, Alcatel-Lucent sold his enterprise business to China Huaxin. Since october 2014, ALE offers communication, cloud and networking solutions for business of all sizes. More than 2700 employees in 100 countries and 2900 partners serve solutions for more than 830000 customers worldwide. ALE offers solutions for unified communications and collaboration, which benefit from intelligent and converged networks. Solutions that scale from the local office to the cloud. Unified communication and collaboration solutions include business telephony solutions (e.g. voice, video and conferencing across the enterprise), mobility solutions (e.g. wired and wireless voice and unified communications across the enterprise and across devices) and collaboration solutions (e.g. cloud or on-premises web conferencing).