Problems with 3G HWIC as Backup Interface

[Sailorderrick]

Good Afternoon

I am trying to configure a 3825 router and a 3G HWIC, with the gi0/0 WAN interface as primary and the cell0/2/0 as secondary. The gi0/1 interface is subdivided into approximately 10 sub-interfaces.

The primary interface works fine, and when the cellular interface takes over, it also works fine. The issue comes when the primary interface comes back online. For whatever reason, the primary interface does not route, and the internet drops.

I suspect I have something wrong in the routing table or the NAT.

Any help is GREATLY appreciated!

Rgds

[Sailorderrick]

Hi Rick

It is 100mbps, but the laptop is coal fired. It is about ten years old and has a 100mbps nic in it.

Unfortunately, I don't have my usual laptop with me, and there are no computers near the VSat.

cheers

Derrick

[Sailorderrick]

Hi Rick

I have included the output of the show controller command in the attachment, for both gi0/1/0 and gi0/3/0.

Cheers

Derrick

[Richard Burts]

Derrick

would you post output of show interface g0/0 when you have the V-Sat connected to that interface and communicating successfully?

HTH

Rick

[Sailorderrick]

Hi Rick

Here are the outputs of Show IP INT BRIEF and SHOW INT gi0/0

Cheers

Derrick

[Sailorderrick]

Hi Rick

Helps to attach the file.

Cheers

Derrick

[Sailorderrick]

Hi Rick I just swapped the cable from the V-Sat into Gi0/0 and I have connectivity. I have to figure out if it is connected to the VSat or it connected to the GSM after there was no connection to the VSAT. (Should have deleted the backup command before I tried this) OK, I checked it with tracert and it was definitely going out over the VSAT (192.168.5.1). So there is definitely something amiss with those other two interfaces. Cheers Derrick

[Sailorderrick]

Hi Rick

Here is the present configuration file as well.

Cheers

Derrick

[Richard Burts]

Derrick

Thank you for the output of show interface and for the current config. My guess at the problem with V-Sat reflects the differences between Gig0/0 and Gig0/1/0 or Gig0/3/0. Gig0/0 does negotiate speed and duplex. The other interfaces do not negotiate. Gig0/0 negotiated speed of 100. The other interfaces just operate at Gig speeds. I am guessing that V-Sat may not support Gig speeds.

HTH

Rick

[Sailorderrick]

Hi Rick
That sounds very plausible. I will head over to the ship in the morning and swap those interfaces around and see if that solves the V-Sat issue. The other thing with the vsat is I need to send some traffic out one interface and other traffic out the other. Thus, I had broken everything down into various VLans. Is it possible to setup two more IP routes, any 20 and 30 and send them to different interfaces at one time? This was the original intention for Gi0/1/0 and Gi0/3/0.
By the way, the cellular interface required the static route to work correctly, so it looks like it may need to be static routes with administrative distances.

Cheers
Derrick

[Sailorderrick]

HI Rick

I swapped the inputs for 0/0 and 0/1 with 0/1/0 and 0/3/0. No joy. I have included the config file. I even set the switchport on the 3750-x to 1000mbps and full duplex just to ensure that the port supplying 0/1/0 was not trying to negotiate anything. Still didn't work. The subinterfaces showed IP address and that they were up, but no data moved. I put everything back and the system with the cable modem and the backup cellular card worked fine again. 

I think it is about time to upgrade to a 3900 series and a EHWIC-1GE-CU. 

In the meantime, is it possible to set up split access lists and routes to allow two interfaces to share VLAN outputs? What I mean by that is: Can I send VLAN traffic as we are presently doing, out one interface and then split it between two interfaces on the V-Sat? The reason being is that business would go out over an "Fast" interface, which is metered (and billed accordingly) and the balance of traffic would go out over another interface that is unmetered, but much slower and throttles itself as more data is put out over it. This is usually used in conjunction with a username and password and has a limit on the bandwidth per person per day.

Thanks Rick

Cheers

Derrick

[Sailorderrick]

Forgot the file.

[Richard Burts]

Derrick

I am a bit confused. Earlier in the discussion you told me "I just swapped the cable from the V-Sat into Gi0/0 and I have connectivity."

Now you are telling me "I swapped the inputs for 0/0 and 0/1 with 0/1/0 and 0/3/0. No joy."

To me it sounds like you swapped once and it worked and you swapped again (at least for G0/0) and it did not work? Am I misunderstanding something?

I can perhaps expect issues about G0/1 since it is set up to connect to a switch trunk. But I am not sure what is the deal with G0/0.

Also can you tell me some more about this 3750 switch? This is the first that I have heard of it. (Perhaps I should have known that you had a switch since G0/1 is configured to connect to a switch trunk. But I have not thought of your issues as involving a switch. So now I need to know a bit more about what it is doing, and about what network devices are connected to it)

HTH

Rick

[Sailorderrick]

Hi Rick

I swapped out the gi0/0 for 0/1/0 and 0/3/0 for 0/1. The two VSat interfaces worked, bu the other two interfaces were up/up but I couldn't ping anything. So there is obviously something wrong with those HWIC-1GE-SFP interfaces, whether it is as designed, or they are defective. (Probably they are not designed to do what I need them to do)

There are actually two switches in behind the router. There is a 3750X that connects to a 4948 in the Lab. The 3750-X also connects to all the cabins and control spaces on the vessel as well the the Ubiquiti APs we have on the vessel. The 4948 provides connections for the personnel using the lab and connects to the 375X via a 4 line fiber etherchannel.

Everything internal to the ship works fine, no issues at all. The only problems are the connections to the outside world.

I have reset everything back to pre-weekend connections and configuration, so gi0/0 connects to the cable modem, and 0/1 connects to the internal network. 0/1/0 and 1/3/0 don't do anything at the moment, although they are physically connected to the V-Sat.

I am waiting to get a 2951 and see if I can get three interfaces operational. If so, I will get in an EHWIC-1GE-CU and see if I can get the fourth interface up.

Could be a couple weeks.

Any thoughts with regard to splitting the access lists to allow me to use the two separate interfaces on the V-Sat simultaneously?

Cheers

Derrick

[Richard Burts]

Derrick

I am thinking about this statement: "I swapped out the gi0/0 for 0/1/0 and 0/3/0 for 0/1. The two VSat interfaces worked, bu the other two interfaces were up/up but I couldn't ping anything. So there is obviously something wrong with those HWIC-1GE-SFP interfaces"

It is good to know that the VSat interfaces did work. When they were swapped what did 0/1/0 and 0/3/0 connect to? I am wondering about the possibility that whatever they were connected to might not support Gig speeds. (and in that case it might be that they are not capable of what you want them to do)

Does your 3750 have any interfaces that are Gig? If so I wonder whether things would work better if you connected 0/1/0 and 0/3/0 to Gig interfaces. You could configure a new vlan on 3750 and connect the cable modem and 0/1/0 in that vlan and you could configure the interface where 0/3/0 is connected as a trunk, and configure at least one sub interface for a vlan connection for testing.

I am not clear what you are asking with this "Any thoughts with regard to splitting the access lists to allow me to use the two separate interfaces on the V-Sat simultaneously?" Which access lists are you asking about? Once we get the VSat interfaces working there are several options we can consider. The easy option is to have 2 default routes, one pointing to each VSat interface. As I mentioned in an earlier response it may be that the DHCP set up for those interfaces by the provider would include a default route. If not then you could configure default routes pointing to each VSat interface. With 2 active default routes some traffic would use one while other traffic would use the other. 

There are some other features that can direct traffic between interfaces, such as Policy Based Routing, or Performance Routing. But if implemented these features would always try to direct traffic to those interfaces, but you do not want that to be active if you are using the cable modem or the cellular. And I do not know of a way to invoke PBR or PfR only when you are using VSat.

HTH

Rick

[Sailorderrick]

Hi Rick

The 3750X has all gigabit ethernet ports, and I even went in and forced 2/0/24 on the switch to 1000mbps and full duplex just to make sure that it was connecting at gig speed when I connected it to 0/1/0. It didn't work. It showed as up/up but I couldn't ping anything in behind it. When I plugged it back into the 0/0 interface and reset the config, everything that had worked prior to the introduction of the 2x HWIC-1GE-SFPs worked again. Those cards are giving me fits. I am going to take one home and play with it a bit.

I am ordering up a 2951 this morning and will give that a go once it arrives. It will take 10 days to two weeks to pitch up. It has a 256Mb PVDM-3 in it as well as an FXO card, so it will allow us to move to VOIP phones as well, once installed.

Trying to get info as to how the V-Sat is internally configured isn't easy, but I will see what I can get out of them with regard to static routes, etc. As I mentioned, it would be important to set it up so certain vlans went over the 192.168.5.1 interface and the rest over the 192.168.6.1 interface. (Due to the way those networks are configured on the VLan.)

Cheers

Derrick