Cisco – Define default GW based on source

Was recently working on a project for a client where the client needed to route traffic from a specific network over a T1 and send the rest of the traffic out the default gateway of the router.  In order to accomplish the task I configured policy based routing on the 2911 as follows:

interface GigabitEthernet0/0.4 Read More

Cisco 7960G 3.x Firmware Upgrade Issues

Working on a project to bring a batch of Cisco 7960G phones online with a newer 7.1 CUCM server.  The issue is that the phones were donated, and although new in the box they were using just about every firmware version from 3.x to 8.x, SCCP and SIP.  The newer revisions were simple enough to manually upgrade via TFTP, but the 3.x revisions absolutely would not upgrade. We tried upgrading from 3.x to 5.x, 7.x, etc with no luck.  We would have liked to upgrade them from 3.1 to a newer 3.x revision, but all of those files from Cisco are packaged in an exe intended for CME.  This limited our options.  Finally found an obscure way to get around the UAL conflicts.

Workaround upgrade from 3.x to 7.x SIP then back to SCCP. Read More

Cisco Stackwise Port Flapping

I recently was confronted with a stack of six Cisco 3750X switches that were experiencing intermittent outages.  The symptoms were random, but included switches being removed from the stack randomly, PoE drops, and full blown switch crashes with reloads.  If anyone has worked with Cisco stacks, you know how long it takes the entire stack to reload and elect a new master.

Troubleshooting the situation, I found that the switch stackwise ports were flapping.  All of them were reporting up/down notifications at random intervals. Read More

Cisco StackPower – Port Issues

I have recently been battling with Cisco Stackpower issues and commands that have been difficult to find. In one environment the company uses 3750X series switches exclusivly in large stacks to avoid a spending cap on single items. Instead of buying blade switches we stack 24 port gig PoE 3750X switches. As an added benefit, with Stackpower we can make the switches redundant without buying additional power supplies. They will also distribute power if PoE devices are unevenly distributed to one switch or the other. Unfortunately when configuring Stackpower, not all ports are active at first, and sometimes the power sharing mode may be configured as something other than “sharing” by default.

A good overview for Cisco’s Stackpower can be found here: Cisco Stackpower Whitepaper Read More

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