ATA 187 Resets Unexpectedly | Cisco Systems OL-21035-01 manual

Chapter 6 Troubleshooting and Maintenance

ATA 187 Resets Unexpectedly

If users report that their phones are resetting during calls or while idle on their desk, you should investigate the cause. If the network connection and Cisco Unified Communications Manager connection are stable, a Cisco Unified IP Phone should not reset on its own.

Typically, a phone resets if it has problems connecting to the Ethernet network or to

Cisco Unified Communications Manager. These sections can help you identify the cause of a phone resetting in your network:

•Verifying Physical Connection, page 6-5

•Identifying Intermittent Network Outages, page 6-5

•Verifying DHCP Settings, page 6-5

•Checking Static IP Address Settings, page 6-6

•Verifying Voice VLAN Configuration, page 6-6

•Eliminating DNS or Other Connectivity Errors, page 6-6

•Checking Power Connection, page 6-7

Verifying Physical Connection

Verify that the Ethernet connection to which the ATA 187 is connected is up. For example, check whether the particular port or switch to which the phone is connected is down and that the switch is not rebooting. Also make sure that there are no cable breaks.

Identifying Intermittent Network Outages

Intermittent network outages affect data and voice traffic differently. Your network might have been experiencing intermittent outages without detection. If so, data traffic can resend lost packets and verify that packets are received and transmitted. However, voice traffic cannot recapture lost packets. Rather than retransmitting a lost network connection, the phone resets and attempts to reconnect its network connection.

If you are experiencing problems with the voice network, you should investigate whether an existing problem is simply being exposed.

Verifying DHCP Settings

Follow this process to help determine if the phone has been properly configured to use DHCP:

Procedure

Step 1 Verify that you have properly configured the phone to use DHCP. See Configuring Startup Network Settings, page 3-4for more information.

Step 2 Verify that the DHCP server has been set up properly.

Step 3 Verify the DHCP lease duration. Cisco recommends that you set it to 8 days.

Cisco Unified IP Phone Administration Guide for Cisco Unified Communications Manager 8.0

	OL-21035-01	6-5

OL-21035-01 specifications

Cisco Systems OL-21035-01 refers to a specific product or course pertaining to networking technologies offered by Cisco. While details of OL-21035-01 may allude to various learning modules, let’s explore its primary features, technologies, and characteristics that highlight the significance of Cisco’s offerings in the IT landscape.

At its core, OL-21035-01 encapsulates essential networking principles and is likely part of Cisco's extensive training portfolio focused on solidifying foundational knowledge in networking. One prominent feature includes a comprehensive curriculum that covers advanced routing and switching concepts. This ensures participants are well-equipped to manage and maintain modern network infrastructures, which are critical in today’s connectivity-driven world.

The learning materials may also leverage dynamic teaching methodologies, engaging participants through simulations and practical labs. This experiential learning approach allows individuals to demonstrate proficiency in configuring Cisco routers and switches, troubleshooting network problems, and implementing strategies for optimizing performance.

In terms of technologies, OL-21035-01 aligns closely with modern networking trends such as Software-Defined Networking (SDN), Internet of Things (IoT), and cloud computing. Understanding these technologies is essential as organizations increasingly rely on scalable, flexible, and intelligent network solutions. The program may also delve into Cisco's proprietary technologies like Cisco IOS, which is fundamental for managing network devices.

Another characteristic of OL-21035-01 is its alignment with industry standards and best practices. This ensures that professionals undergoing training are prepared for real-world scenarios they will face while managing enterprise-level networks. Cisco certifications, often obtainable through these courses, are recognized globally and can significantly enhance career prospects.

Additionally, OL-21035-01 stresses the importance of security in networking. Participants learn about robust security protocols, firewall configurations, and strategies to protect networks against cyber threats, ensuring that they remain resilient in the face of growing security challenges.

Lastly, Cisco’s emphasis on continuous learning is mirrored in the iterative nature of its offerings, encouraging IT professionals to stay updated with the latest advancements in technology. Consequently, OL-21035-01 not only serves as a stepping stone in one’s career but also fosters a culture of lifelong learning, vital for navigating the ever-evolving tech landscape.

In summary, OL-21035-01 embodies a holistic approach to networking education, focusing on critical skills development, contemporary technologies, and a robust understanding of security measures necessary for thriving in the IT sector.