Cisco ISR 1100 — settings, status lights and reset
The ISR 1100 has no default LAN address, and this is the single biggest trap on the model.
The documented default login is admin with the password admin.
Partly verified. The facts themselves are high confidence and sourced to cisco.com. The medium rating is about the question rather than the answer: "ISR 1100" resolves to two Cisco product families with incompatible defaults, so the first thing this page has to do is establish which one you have.
The Cisco ISR 1100 is a router from Cisco, in UK use 2018-present. This page covers the four things people actually come looking for: its settings address, how its login works, what its lights mean and how to reset it safely.
What is the Cisco ISR 1100 gateway address?
The ISR 1100 has no default LAN address, and this is the single biggest trap on the model. Cisco's published factory configuration brings every GigabitEthernet interface up with no IP address, no VLAN interface and no DHCP server, and the default also contains no ip http server. There is nothing listening on 192.168.1.1 or on anything else, so a browser will find nothing. You get in over the RJ-45 console port instead, at 115,200 baud — Cisco notes the console "only supports a baud rate of 115,200". Be careful what you plug into it: Cisco warns that "Power over Ethernet (PoE) enabled cables can damage the console port". The reason you will see 192.168.1.1 quoted for an "ISR 1100" is a naming collision. Cisco hosts the Cisco 1000 Series ISR software guide under an isr1100 URL path, and that guide does describe a day-zero web interface on 192.168.1.1 — but only after a basic configuration with a Vlan1 address and a DHCP pool has been put on the device by hand, and it is a different product from the ISR1100-4G, 6G and 4GLTE branch routers.
What is the default username and password for the Cisco ISR 1100?
Documented fixed default
The manufacturer publishes a single default login for the Cisco ISR 1100, so we can show it:
- Username
admin- Password
admin
On units ordered with Cisco IOS XE the published factory configuration contains username admin privilege 15 secret 0 admin, so it is admin and admin over the console. The same pair is documented for the SD-WAN day-zero web interface. Two qualifications matter. Units ordered with Cisco vEdge OS ship with only a hashed password in the published default configuration, and Cisco does not print the plaintext, so we are not going to invent one — you cannot answer "what is the default password" for this model without knowing which operating system it was ordered with. And the day-zero web interface of the Cisco 1000 Series, which is a different product despite the shared URL path, uses webui and cisco. Cisco flags the weakness itself: "the default password of your Day-0 device is weak. Therefore, for a secure log in, you must reset the password when you first log in."
This only works if nobody has changed it. On a unit that has been in service for a while, someone should have, and if they did then no published default will help you.
What do the lights on the Cisco ISR 1100 mean?
Here is what each light on the Cisco ISR 1100 is telling you, and what to do about it.
| Light | What it means | What to do |
|---|---|---|
| SYSsolid green | Normal operation. | |
| SYSflashing amber | The router is in its boot-up phase. | Wait for it to settle before drawing conclusions. |
| SYSsolid amber | The system is going down, or there is a fault. | Get on the console at 115,200 baud and read what it is saying — that is the only place the reason will appear. |
| SYSoff | The system is off. | Check power. |
| STATUSsolid green | The SD-WAN OMP connection to the controller is up. | |
| STATUSoff | The system is down, or the OMP connection is down. | On a router that is not attached to an SD-WAN controller this light is meant to be dark. It is not a general health indicator, and off is normal for a standalone unit. |
| RJ-45 portsolid green | That port has a link. | |
| RJ-45 portflashing green | Data is passing on that port. | |
| RJ-45 portoff | The link is not connected or is down. | Check the cable and the far end. |
| SFP portsolid green | The SFP port has a link. 6G models, ports 4 and 5. | |
| RSSIsolid green | LTE is enabled with an excellent signal. LTE models only. | |
| RSSIflashing green | LTE is enabled with a good signal, alternating green and orange. LTE models only. | |
| RSSIsolid orange | LTE is enabled but the signal is poor. | Reposition the antennas or move the unit before assuming the SIM or the network is at fault. |
| RSSIflashing orange | LTE is enabled but in error — either no connectivity with the mast or no signal at all. | Check the SIM is seated and active, then the antennas. |
| RSSIoff | The LTE interface is shut down. | |
| SIMoff | No SIM is fitted, or the SIM is offline. LTE models only. | Check the SIM is present and the right way round. |
| SIMflashing | On for a second and off for a second — the unit is in low power mode. |
STATUS is an SD-WAN indicator rather than a health light, so a dark STATUS on a standalone router is normal.
How do you reset a Cisco ISR 1100?
What you lose. write erase removes the entire startup configuration: all routing, access lists, crypto and IPsec configuration, the SD-WAN bootstrap, VLANs and local users. On an SD-WAN unit it also breaks the controller association, so the router has to be onboarded again through zero-touch provisioning or a bootstrap file before it will carry traffic.
- There is a Reset button on the chassis — Cisco labels it in every panel diagram — but Cisco never documents what it does, how long to hold it, or what it destroys, and we are not going to guess at behaviour the vendor has not published. The documented route is the software one: write erase from the CLI. Cisco's own day-zero procedure says "if the router is not in the factory fresh mode, use the write erase option to erase all the configuration from the router".
- Hold it for Not published by Cisco for the physical button..
- Release, and give the unit a few minutes to restart before trying to connect.
This is the one model here with a published light table but no published reset-button behaviour — the inverse of the usual gap.
A reboot is not a reset. A reload keeps the startup configuration. Only write erase clears it, and only a subsequent save makes that permanent.
What if you cannot get into the Cisco ISR 1100 at all?
Yes, and this is the real difference from consumer kit: you can recover a locked router without losing its configuration. Cisco documents a console-based ROMMON password recovery that explicitly covers the ISR1000 family, and it needs physical console access — "in order to perform a password recovery, you must have device console connection", and a remote SSH or Telnet session will not do. The sequence is to power-cycle the router, send the break sequence during boot to reach ROMMON, set confreg 0x2142 so it boots ignoring the startup configuration, reset, then copy startup-config running-config, change the credentials, set config-register back to 0x2102 and save. The one thing that blocks it is no service password-recovery: if that has been configured you can still interrupt the boot, but only by agreeing to reset the device to its default configuration, which deletes config.text and vlan.dat.
If that does not work, a factory reset will always get you in, at the cost of every setting on the unit.
Where this comes from
- Cisco ISR 1100 4G/6G Hardware Installation Guide — Source of the factory default configuration with no IP addressing, the console baud rate, the admin/admin IOS XE default and the light tables.
- Cisco 1000 Series ISR — management interfaces — The day-zero web interface that requires a basic configuration first, and the source of the naming collision this page has to resolve.
- Troubleshoot password recovery on Cisco routers — The ROMMON recovery procedure, explicitly covering the ISR1000 family, and the effect of no service password-recovery.
- Understanding the configuration register — What 0x2142 and 0x2102 do.