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32Mb RAM devices and ROS 6

Posted: Fri Oct 03, 2014 3:36 pm
by Maggiore81
Hello
what do you think about ROS 6.xx and 32Mb RAM devices as RB750 ?

I use just:
system
ipv6
advanced-tools
security
packages and after boot they have about 10mbyte ram free , versus 5.26 that have about 18mbyte free.

Is ROS 6.xx suitable for 32mb devices in the long run, or (as I do now) do I need to reboot them once a week?
thank you

Re: 32Mb RAM devices and ROS 6

Posted: Fri Oct 03, 2014 4:40 pm
by onnoossendrijver
Well, 10MB is not 0MB free :)

It can work fine, but I would monitor RAM usage on the device using SNMMP/Cacti (just like with any other device).

Re: 32Mb RAM devices and ROS 6

Posted: Fri Oct 03, 2014 5:36 pm
by Maggiore81
I already keep track of the ram, and I schedule a reboot every 7 days to be safe.

Re: 32Mb RAM devices and ROS 6

Posted: Sun Oct 05, 2014 10:50 am
by jaykay2342
The question is what can eat up ram once the system is booted? Queues maybe a bit also the connection tracking table. But i think you can have a decent amount of connections before this becomes an issue.

Re: 32Mb RAM devices and ROS 6

Posted: Sun Oct 05, 2014 11:36 am
by Maggiore81
My packages are:
dhcp
system
security
adv-tools
routing

the router does:

OSPF
about 10 firewall rules.
routing from eth1 to eth2 and vice versa
dns cache
nothing else.

Re: 32Mb RAM devices and ROS 6

Posted: Sun Oct 05, 2014 1:10 pm
by jaykay2342
Have you faced any issues due to filled up ram so far? You have around 31% free that's ok , isn't it? I mean why would you expect your router to start consume more ram as it does right now? As long as you not to turn on more features it should not suddenly consume more ram. You might get some extra entries in the routing table or connection table (if you have connection tracking on). But such entries are small and you need a lot of those to fill up the 10M free ram you have at the moment.

Re: 32Mb RAM devices and ROS 6

Posted: Sat Oct 11, 2014 12:42 pm
by Maggiore81
Well.. when I come to 6mbyte free ram I fear that the router could lock up.

I have about 30 simple queues (pcq queues) and nothing else on a RB750... I ended putting 5.26 and I have 14mb free

Re: 32Mb RAM devices and ROS 6

Posted: Sat Oct 11, 2014 1:08 pm
by jaykay2342
Well.. when I come to 6mbyte free ram I fear that the router could lock up.

I have about 30 simple queues (pcq queues) and nothing else on a RB750... I ended putting 5.26 and I have 14mb free
Why are you fearing that? I mean what should suddenly eat all that ram?
Look that's one of my 32MiB router devices. Also short on free-memory. I don't lock up since i'm on 6.X
                   uptime: 18w2d2h32m9s
                  version: 6.10
               build-time: Feb/12/2014 13:46:18
              free-memory: 7.8MiB
             total-memory: 32.0MiB

Re: 32Mb RAM devices and ROS 6

Posted: Sat Oct 11, 2014 11:49 pm
by jarda
7.8mb is fine. Problems start below 5mb of free ram on 32mb devices. They are not able to produce supout file for instance, having problems with responding to snmp, starting to blacklist programs from snmp, running cpu at full and sooner or later restart by watchdog. Generally I would say that 32mb of ram is too low for version 6.xx. Unfortunately.

Re: 32Mb RAM devices and ROS 6

Posted: Sun Oct 12, 2014 11:23 am
by jaykay2342
7.8mb is fine. Problems start below 5mb of free ram on 32mb devices. They are not able to produce supout file for instance, having problems with responding to snmp, starting to blacklist programs from snmp, running cpu at full and sooner or later restart by watchdog. Generally I would say that 32mb of ram is too low for version 6.xx. Unfortunately.
I would not say that 32mb is generally too low as it depends which features you have activated. Have you tried to disable packages you don't need?

Re: 32Mb RAM devices and ROS 6

Posted: Sun Oct 12, 2014 3:54 pm
by jarda
Of course. I only install selected packages if I need them. It means there are no packages that could be disabled.

Re: 32Mb RAM devices and ROS 6

Posted: Fri Mar 13, 2015 1:28 am
by gammy69er
I have been Finding 32mb Devices (and to mention it, the <400mhz devices also - 532's, 333's, 411's etc) are not enough to support ROS 6 - am currently about to run some testing on Downgrades and the likes.

For us - we use the HS system... so big overheads - but I would at this stage recommend that if you have any advanced functions - Queues, HS, OSPF etc. that if you have less than 12 MB free - to look into options.

I have found that most of my systems are shooting up to 100% cpu on Login attempt (as I say, for non-HS this won't be as prevalent) - if I have a 64MB 751u (per-say) then it chugs a little more RAM and poops out a login page for the end user. CPU Usage Drops back to norm and we are all good. Units Showing ~28 mb free normal running (~36mb used)

If I have a 32MB 751u (strangely enough my supplier has had both - and all listed as the same model on their site) - I have between 10 and 6 mb free - and when I get a HS user - it gets constipated (sorry for the references - but was the train of thought) - and sometimes gets the page out - but takes longer to drop back in CPU. if it has had a few of these - it "Faints" - watchdog kicks in and reboots. This does also happen Even when the device is not being used - just no where near as often.

I finally came to this conclusion 2 weeks ago after several months of tracking it down - but have successfully change 5 HS since with great results - and roughly 10 HS before I figured out the issue (Most with 951U or mAP) - of the 10+ prior to finding out the cause - several had been replaced with 751u with fresh configs which proceeded to fail - however same config on a 951u worked.

I have had Successful Upgrades of 411AH's, 2011's, 800's. All with More than 400Mhz and 64MB.

for the small cost - I recommend upgrading HW to mAP/951U (in saying that mAP is a pain with the small flash - Netinstall Upgrading and the likes) - but to save costs - possibly Downgrading to 5.x will keep you running in the meantime. of course - no real tech will recommend losing features/security by Downgrade - so I really recommend New RB.

Re: 32Mb RAM devices and ROS 6

Posted: Fri Mar 13, 2015 12:24 pm
by normis
7-8MB of RAM is enough for RouterBOARD to run RouterOS v6. I have seen no issues. Maybe the problem is caused by something else? I suggest sending supout.rif file to support

Re: 32Mb RAM devices and ROS 6

Posted: Fri Mar 13, 2015 12:44 pm
by janway
Hi!

Please see attached diagrams. I'm trying to setup a hotspot wifi-network on a site. The network consist of a tech/admin part with address 192.168.10.xxx/24 and a guest/hotspot part with address 192.168.20.xxx/22.

The hardware consist of a RB433 that's running the hotspot service. The hotspot is running on the bridge for the local AP on the RB433 and the VPLS bridge to RB951 (used as external AP). Another local network adapter on the RB433 is used to bridge the network with an external SXT-device to a RB951.

When the hotspot service is disabled, users can login and have Internet access on the guest/hotspot network on both AP. Apparently everything is working well in this situation.

Re: 32Mb RAM devices and ROS 6

Posted: Fri Mar 13, 2015 1:11 pm
by mars
32meg memory is not enough for ros6 specially when you do a lot of data we had so much problems that we stopped using 32meg devices
the rb711 was the worst

Re: 32Mb RAM devices and ROS 6

Posted: Fri Mar 13, 2015 3:31 pm
by jarda
7-8MB of RAM is enough for RouterBOARD to run RouterOS v6. I have seen no issues. Maybe the problem is caused by something else? I suggest sending supout.rif file to support
According to my observations problems starts below 6mb free ram and 5mb is critical. Using router with home settings, no queues but some tunnels, 20 static routes, 20 firewall rules and dude polling easily takes 32mb ram equipped router with 6.27 to knees. I suspect it goes to swap or does noone knows what until it is restarted. Then beginning at 7mb free ram and going slowly down. This applies to all 32mb mipsbe/mipsle devices I had in my hands. I never saw working router having less then 4mb free ram.

For what reason is the ram reserved and not used? Because otherwise it has to work without any impact on performance till whole ram capacity is exhausted.

Don't you think?

And of course, there is no way to make supout at these situations because just supout generation normally needs additional 1-2mb of ram...

Re: 32Mb RAM devices and ROS 6

Posted: Sun Mar 15, 2015 11:04 pm
by gammy69er
7-8MB of RAM is enough for RouterBOARD to run RouterOS v6. I have seen no issues. Maybe the problem is caused by something else? I suggest sending supout.rif file to support
According to my observations problems starts below 6mb free ram and 5mb is critical. Using router with home settings, no queues but some tunnels, 20 static routes, 20 firewall rules and dude polling easily takes 32mb ram equipped router with 6.27 to knees. I suspect it goes to swap or does noone knows what until it is restarted. Then beginning at 7mb free ram and going slowly down. This applies to all 32mb mipsbe/mipsle devices I had in my hands. I never saw working router having less then 4mb free ram.

For what reason is the ram reserved and not used? Because otherwise it has to work without any impact on performance till whole ram capacity is exhausted.

Don't you think?

And of course, there is no way to make supout at these situations because just supout generation normally needs additional 1-2mb of ram...
Cheers for the Backup jarda - see you are quite respected round these parts :)

And Normis - you too - cheers for the input - but the Numbers aren't lying to me - if the same config that worked well on RoS 5 causes problems on RoS 6 - I would believe it to be the System - not the config.

Also - the simple fact is that on a full Config - 32mb router has ~7-4 mb free (up to 28mb used) - yet I have not see a 64mb router with any more than 28 mb free - that is 36 used - Same for 128's usually 92-88 mb free - that's up to 40mb used - as you say, yes system runs - however with all of the extra calls to RAM to move thing around while moving things through for the units that don't have enough (cause you can see RoS 6 happily uses more than 32mb) it requires a lot more CPU work - on a 2-3 GHz PC - this is a dawdle - yet when we are talking 400mhz clock cycles - were a going back to issues we were having in the 90's with PC's and Speed. That is why pc's now have more ram - and I assume why routerboards now do also.

Either way - as I say, my findings have been >64mb = Good, <32mb = bad for total hardware RAM vs RoS 6. I will look into the implications of flicking in a supout at some stage - comparing the versions of HW - but for the moment - I have a fair amount on - and no issues :)

Re: 32Mb RAM devices and ROS 6

Posted: Tue Mar 17, 2015 5:57 am
by phendry
I suggest sending supout.rif file to support
As others have mentioned, the problem is that when this occurs the device is unable to produce supout.rif. We had standardised on v5.26 for a long time but as newer boards have been added into the network we have needed to move towards v6. After some testing we had started rolling v6.18 on to a few hundred devices. We began seeing random radios drop with watchdog timer being the issue and we would see at least 2 devices a day affected. We have seen this on RB911's, RB711's and RB411's but not seen on any RB411AH's, RB411A's, RB333's, RB2011's, RB800's, RB1100AHx2's, CCR's, RB922's or the newer AC version of the RB911's. Only difference seems to be 32MB ram as all the others have more.

Re: 32Mb RAM devices and ROS 6

Posted: Wed Mar 18, 2015 4:02 am
by phendry
RAM Issue.PNG
Located a device that was running low of free memory. Attempted to create supout.rif causing router to reboot due to watchdog as expected.

Re: 32Mb RAM devices and ROS 6

Posted: Thu Mar 19, 2015 8:45 pm
by kmok1
+1

But I m hoping MK can do a better job with ROS7 on this issue.

http://forum.mikrotik.com/viewtopic.php?f=19&t=94196

Re: 32Mb RAM devices and ROS 6

Posted: Fri Apr 17, 2015 12:31 am
by gammy69er
Just a little more fuel for the fire...

Image

It's not often I get the full description of the failure like this, usually it's just "router was rebooted without proper shutdown" or "router was rebooted without proper shutdown by watchdog timer"

This is yet another unit on my Upgrade List - with the low costs, it's not too much of an issue. Still yet to find a suited use for the smaller units - managed switched comes to mind :)

I hear a lot of calls to repair ROS - but at the end of the day - the cost of h/w vs the tech now available vs the advanced functionality - I am happy to upgrade - to get a better unit with at least a chance of another 5-10 years. The only thing that annoys me is that Ubiquiti has a dual core 800mhz+ unit for less than $100... Still prefer the functionality of ROS though

Re: 32Mb RAM devices and ROS 6

Posted: Fri Apr 17, 2015 1:38 am
by phendry
The cost is not the problem. It's the logistics when you have 400 32MB devices in the field. Rolling back (again) to v5 :(

Re: 32Mb RAM devices and ROS 6

Posted: Thu Apr 23, 2015 1:11 pm
by gammy69er
Sorry Phendry, you are 100% correct... A roll back destroys config and makes a mess. Perhaps a new "Rollback" version would be a quick way to get the punters happy (potentially a v6.99 say, that "upgrades the router" to a point where it is at 5.21 or less) and a disclaimer on all current versions to warn of this potential hassle. It is fairly well documented on the forums, but I know most of us don't read these before we have the issues.

Re: 32Mb RAM devices and ROS 6

Posted: Thu Apr 23, 2015 2:38 pm
by phendry
Rolling back isn't a particular problem. The issue is that there are features in v6 we would like to use which we can't when such a large amount of devices have this memory problem. We have even seen the same problem with RB411AH boards that have 64MB although this isn't so often. What is it in v6 that causes this memory leak that isn't in v5?

Re: 32Mb RAM devices and ROS 6

Posted: Sat Jun 11, 2016 8:28 am
by gammy69er
God - i'm so late with the Replies - but my comment to you sir would be that there isn't a memory "Leak" as such... but the is more features, which take more memory, and if you don't increase the device's memory, and the devices "Out of Memory" minimum conditions remain the same as previous (but actually more than likely increase in requirement due to the added features), then you run a higher risk of getting to an Out of Memory state.\

Just for anyone who does come over this - i can happily state that all of the device that I have purchased recently are sitting quite happy on ROS 6.XX.  this includes:
RB951U
RB951G - even have one of these with 200mbps Fibre, 2 Hotspots and pppoe-server with 6-8 sessions over Ubiquiti Backhaul
mAP
hAP
RB750P-PB (Outdoor Power Box - Sooooo handy)
RB850Gx2
RB3011 (I DO LIKE this one :D)

Also, it is sitting quite well on RB433AH and RB493GAH - but these things were the BEAST MODE when they were released. 

Almost all of My 75x's, 411's, 532's, 433's (non AH) and RB600's have been decommissioned/superseded now.  In saying that, i do still have a 751U - 64MB out there running well.  My last RB800 is getting the boot next summer - for a RB3011.

Oh, and CCR as usual - God Mode.

So, basically - what i am saying is stick to 64MB + for Hotspots (if you hadn't gathered already).  Basic LAN's with firewall can survive on smaller (why the hAP-Lite exists), but for the few $$ more, the hAP, or the 951, is totally the way to go for WISP or Business.  Larger Hotspot Sites (~200-500 connections daily) - then RB850 is King, larger than 500, 3011 is Beast - and for the maximum, CCR is God - imho :)