Uplogix provides remote-site lifeline
Envoy and EMSFollow @pvenezia
It’s the bane of remote-site network administration: the moment you realize that the routing change you just made on a remote router has locked you out of the site entirely and knocked the site offline. It’s not necessarily a case of poor admin skills, but more likely a simple mistake.
Uplogix’s Envoy is designed to provide a parachute when mistakes happen, by automatically attempting to reset the configuration of a network device to a last-known good state, or at least by providing dial-up/dial-back access to any connected device.
Hooking Up the Hardware
The Envoy is a 1U rack unit with both RJ45 serial ports and standard 10/100 Ethernet ports, plus a dedicated out-of-band management port, switchable PDU control port, an embedded 56k modem, and a small LCD management console in the front. Installation is simple, using standard UTP cable to connect to RJ45 serial console ports on network devices as well as to the Ethernet management interfaces found on many switches, and setting an IP on the device via the front-panel console.
Armed with these connections and suitable configurations, all of your company’s connected network devices can now be managed centrally from the Envoy, both manually and automatically. However, Envoy works only with network devices that Uplogix supports. Such devices include Juniper routers, 3Com SuperStack switches, TippingPoint IDS, Cisco IOS, CatOS, and PIXOS, and some Nortel routers.
The Envoy is built on a Linux core, booting from an internal hard drive (the Achilles’ heel of network appliances), and is written completely in Java. The CLI is accessible only via SSH; it is quite rudimentary and vaguely based on the Cisco IOS CLI. There is no Web management UI on the Envoy itself, as the EMS (Envoy Management Station), which ships on a Dell 2U server, handles all management tasks.
In the lab, I connected a four-port Envoy unit to three Cisco switches: a Catalyst 4506 with a Supervisor II+10GE management blade, a Catalyst 4948-10G, and an older Catalyst 2924XL. The 4506 blade had a 10/100 management port cabled to the Envoy; the other switches relied solely on the console port for communication. I also connected a four-outlet Server Technology switchable PDU to the Envoy and each switch.
In the CLI, I defined each console port on the Envoy with a name and various connection parameters such as baud rate, stop bits, console passwords, and PDU outlet number. The Envoy pulled relevant data from the switches, such as the running configuration, startup configuration, and uptime, which appeared in the GUI.
The EMS Web GUI is adequate, providing at-a-glance device health and alarm status, task scheduling, device configuration file views, and other rudimentary configuration management tools. You can group devices via filters and push specific configuration commands to devices that meet the filter criteria, such as applying new passwords to every Juniper router.
Under normal operating conditions, the Envoy runs tasks at set intervals to keep up with device configuration changes, availability, CPU and memory utilization, and so on. Also, the Envoy offers a direct link to the console of any connected network device via the Envoy CLI. This allows you to SSH into a remote-site Envoy and assume control of a switch or router’s serial console as if you were there with a laptop and a serial cable. The Envoy can also be configured as a terminal server, and SSH connections on different TCP ports will allow console access to connected devices.