Routing

Hello,

I first of all want to say I am brand new to this community and to Juniper devices in general. I have some experience with GUI-based SonicWall, Cisco, and NetGear devices. I have three years in the industry in small business scenarios usually being the "go to guy" not getting a lot of learning growth unless I read through whitepages myself. That being said I am not an expert of any strech but I do pride myself in being a very strong technical thinker and extremely quick learner. I am new with the company only being employed for little under a month and I am still learning physical and logical layouts. However, I traced every cord of the following location.

Backstory:

If you are on spiceworks you can get the long theatrical version here. For those of you who want the nitty gritty here you go.

I have a branch location (2 blocks from corporate) who recently switched off of an MPLS system into an IPSec 15/2M Cable connection from TWC Business Class. Previously they had no issues, they used the MPLS to access an ERP (distribution software) back at Corporate and it's a fairly low bandwidth requirement I've been told 500kb/s, it's an old dos based system. Since then they have got periodic moments of extreme latency where the terminals they are inputting tickets into have 5-10 second delay on inputting data and then catches up and continues at full speed appearing instant like it should. This happened for about 2-5 minutes once a day at random times during the day, best I can tell around 11am. This happening before I started with the company mind you. Until one day I come in and the whole branch is crawling all day long, long story short. TWC dispatches a tech and an area crew to our location. They sign off on the line to our building as working properly and replace our modem (long story). The connection seems to be ok for a few days then the sags come back again, about once a day 2-5 minutes. Eventually recently it's getting up to 3-4 times a day for 2-5 minutes and seems to be more frequent although that's speculation. Being a construction company the employees are not too keen on details.

The thread on Spiceworks got a few replies one guy stating that I should look into configuring the MTUs down to around 1400. I have been searching and not found an easy adjustment for general setting to MTU device wide. (SSG-5) I am out of my element and looking for some advice and an avenue to head. I don't know if this is the right forum to post in, I tried to be thoughtful.

I am aware I will probably need to generate some logs, config files, etc for you guys to give me any good leads but since the ISP seems solid I am starting to look internally as this SSG-5 is a new router in the traffic route back to corporate and to the server, previously was MPLS and smooth. This also all henges on adding more VoIP lines etc onto this location so cleaning up latency and potential packet drops are huge when we are talking about voice in the network. That's potential lost sales.

Thanks guys been poking around you seem like a great community can't wait to be able to give back!

Seth

Hey Seth - welcome to Juniper - though what a way to have to come meet us all. First of all this needs to be posted in the "ScreenOS Firewalls" forum for maximum visibility and assistance. 

I personally don't do ScreenOS anymore but from memory if you navigate to the Interface <Network / Interfaces > you can change it there. 

Having said that, and not having read your whole thread changing the MTU might help but you are describing very random failures and I can't see MTU coming into play unless the paths for the data traffic get changed and you are intermittenly passing through network devices that can't handle the current settings. 

However I am sure much smarter folk than me can help once your inquiry is in the right forum.

Thank you very much I will move it at once!

Take care.