Cisco ASA 9.2 on Cisco ASA 5505 with Unsupported Memory Configuration Fail

EDIT: 16/11/2015 – It looks like it now works. I am currently running asa924-2-k8.bin on my 5505s, with my 1GB sticks of RAM, and it hasn’t complained! 🙂

The Cisco ASA 5505 officially supports a maximum of 512MB RAM.

Last year I wrote a post detailing a small experiment I done where I upgrade both my Cisco ASA 5505s to use 1GB sticks of RAM, double the officially supported value.

Since then, it has worked great and both boxes have been chilling out in my rack, but recently Cisco released ASA 9.2.

The full list of new features and changes can be read in the release notes, but the feature I was most excited about was BGP support being added.

The ASA has had OSPF support for some time, but it was lacking BGP, which I always thought was a feature it should have. Now that it has been added, I was quite excited to play with it!

So I grabbed the latest 9.1 image (asa921-k8.bin), and dropped it on both my ASAs. Switched the bootloader configuration to load the new image. Next I reloaded the secondary device, and waited for it to come back up. Half an hour later, nothing. So I connected a serial cable to see what’s up, and to my surprise I find that it not doing anything. It’s just stuck saying:

Loading disk0:/asa921-k8.bin...

Initially I wasn’t really sure what was causing this, so I tried switching out the RAM and putting the stock 512MB stick that I got with the box, and magic! It worked.

I’m quite disappointed that my 1GB sticks won’t work with 9.2, but it’s not a huge loss. My Cacti graphs I only use around 300MB anyway!

Memory Usage on my Cisco ASA 5505s
Memory Usage on my Cisco ASA 5505s

I’m going to have to buy a 512MB stick for my secondary ASA, as now they refuse to be in a failover configuration due to having different software versions and different memory sizes.

Alternatively, I’m thinking of just replacing these boxes with something else. My ISP (Virgin Media) will be upgrading my line to 152Mbit/s later this year. The ASA 5505 only has 100Mbit ports so I will be losing 52Mbits! I don’t want that, so I’ll have to get something faster. I’ll probably either go with just a custom Linux box with IPtables, or maybe a virtual ASA now that Cisco offers that! 🙂

Home Lab: Added a Cisco 3845 ISR

Why? Well, I wanted more ISRs in my home lab.

That, plus my ISP (Virgin Media), will be upgrading my line from 120mbit to 152mbit in the second half of 2014. Looking at the Cisco docs, the 2851 ISR I am using can only do up to around 112mbit/s.

Although there is a long time for my ISP to go forward with this upgrade, I saw the 3845 going reasonably cheap on eBay, cheaper than what I expect it will be next year when my ISP WILL have upgraded my line. So, I decided to just buy it now. 🙂

I am really starting to have a problem with space for my home lab.  My rack is already pretty much fully populated, so I now have equipment on top of, and surrounding my rack. I don’t really have space for a second rack at the moment, so it looks like I can’t expand my lab any more for a while. Oh well. 🙁

Home Lab Network Redesign with Mikrotik Routers

I have two cable connections from Virgin Media coming into my house due to some annoying contract problems.

I originally had one line on the 60Mbit package, and the other on 100mbit, but when Virgin Media upgraded me to 120mbit I downgraded the 60mbit line to 30mbit to reduce costs.

Since I got into this strange arrangement with Virgin Media, I have been using a Cisco 1841 Integrated Services Router on the 30mbit line, and a Cisco 2821 Integrated Services Router on the 120mbit line, but I found that I wasn’t able to max out the faster line using the Cisco 2821 ISR. Looking at Cisco’s performance sheet, the Cisco 2821 ISR is only really designed to support lines of up to around 87 mbit.

So naturally, it was time to upgrade! Initially I wanted to get a faster Cisco router, but looking at the second generation ISRs, it’ll be a bit pricey!

I did actually upgrade all my 7204 VXRs to have NPE-400 modules, which according to the performance sheet should do around 215 mbits, but the 7204s are extremely loud, and I only switch them on when I am using them.

Michael and Jamie have always been talking about Mikrotik routers so I figured since Cisco is a no go, I’ll give Mikrotik a chance. I ended up buying two RouterBOARD 2011UAS-RM from WiFi Stock.

To put the RB-20011UAS-RM boxes in, I decided I was going to restructure my network a bit. I will be making a series of posts discussing my re-designed network.

My goals for the redesign were as follows:

  • The RB-2011UAS-RM boxes will only function as edge routers, encapsulating traffic in GRE tunnels, and that’s all.
  • There will be a link between both edge routers, with a BGP peering for redirecting traffic should one of my lines go down.
  • They will have GRE tunnels to all my dedicated servers/VPSs.
  • I will use Quagga on all dedicated servers, and VPSs outside my network to create BGP peerings with my edge routers.
  • I wanted to route all my internet out of a server I currently have hosted with Rapid Switch, so BGP on the RapidSwitch box (called diamond) will have to push down a default route.
  • I wanted to use my Cisco ASA 5505 Adaptive Security Appliance as firewalls between the edge routers and the core.
  • I recently bought a Cisco 2851 Integrated Services Router, which I will use as a “core” router.
  • I wanted as much redundancy as possible.

In my next post I will create a diagram of what I will be doing, and discussing the setup of the server I have hosted at RapidSwitch.

As I have never used Mikrotik routers before, I will also attempt to discuss my experiences of RouterOS so far as I go along.

Connecting to Usenet via Two Internet Connections

As I mentioned in a earlier post, I have two connections from Virgin Media at home and I wanted to use them both to grab content from usenet.

My Usenet provider is Supernews, I’ve used them for a couple of months, and from what I understand they are actually just a product of Giganews.

Supernews only actually allow you to connect to their servers from one IP per account, so even if I had set up load balancing to split connections over both my connections, it would not have worked very well for usenet as I will be going out via two IP addresses! So for this reason I decided to take another route.

I have a dedicated server with OVH which has a 100mbit line, my two lines with Virgin Media are 60mbit and 30mbit, so I figured if I route my traffic out via my dedicated server, I should be able to saturate my line when usenetting. 🙂

So the way I done this was to create two tunnels on my Cisco 2821 Integrated Services Router going to my dedicated server, one tunnel per WAN connection and basically “port forwarding” port 119 and 443 coming over the tunnels to go to Supernews. It’s working great so far and saturating both lines fully!

So the way I done this was as follows. First I setup the tunnels on my trusty Cisco 2821 ISR:

interface Tunnel1
description Tunnel to Dedi via WAN1
ip address
no ip redirects
no ip unreachables
no ip proxy-arp
ip tcp adjust-mss 1420
tunnel source GigabitEthernet0/0.10
tunnel mode ipip
tunnel destination

interface Tunnel2
description Tunnel to Dedi via WAN2
ip address
no ip redirects
no ip unreachables
no ip proxy-arp
ip tcp adjust-mss 1420
tunnel source GigabitEthernet0/1.11
tunnel mode ipip
tunnel destination

That isn’t the complete configuration, I also decided to NAT my home network to the IPs of the two tunnels. This was just in order to do it quickly. If I had not used NAT on the two tunnels, I would have to put a route on my dedicated server for my home network’s private IP range. Although this is easy, I was mainly doing this out of curiosity to see if it would work, and to do it without NAT on the tunnels I would have had to figure out how to do policy based routing in order to overcome asymmetric routing on Linux. That can be a project for another day. 🙂

My dedicated is running RHEL6, so to set up the tunnel on the dedicated server I created the relevant ifcfg-tunl* files:

[[email protected] ~]# cat /etc/sysconfig/network-scripts/ifcfg-tunl1

[[email protected] ~]# cat /etc/sysconfig/network-scripts/ifcfg-tunl2

I don’t really want to go into detail on how configure netfilter rules using IPtables, so I will only paste the relevant lines of my firewall script:

# This rule masquerades all packets going out of eth0 to the IP of eth0
iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE

# Forward packets coming in from tunl1 with the destination IP of and a source port of either 119 or 443 (Supernews use 443 for NNTP SSL port) to Supernews' server IP
iptables -t nat -A PREROUTING -p tcp -i tunl1 -d --dport 119 -j DNAT --to
iptables -t nat -A PREROUTING -p tcp -i tunl1 -d --dport 443 -j DNAT --to

# Forward packets coming in from tunl2 with the destination IP of and a source port of either 119 or 443 (Supernews use 443 for NNTP SSL port) to Supernews' server IP
iptables -t nat -A PREROUTING -p tcp -i tunl2 -d --dport 119 -j DNAT --to
iptables -t nat -A PREROUTING -p tcp -i tunl2 -d --dport 443 -j DNAT --to

That’s all there is to it really! Of course I have a more complete rule set, but I don’t really want to go into that in this post!

Next, I just added two servers in my usenet client, one pointing at and the other at And magic! Now both lines will be used when my usenet client is doing its thing!

Note: If you got to the end of this post, I apologize if I make no sense, I was pretty tired while writing this post, and really just wanted to go to sleep. If you have any questions or suggestions on how to do this better, I’d be very interested in hearing them.  :~)

Dead Cisco Catalyst 3560

I’ve been trying to acquire a Cisco Catalyst 3560 as it provides features which are not supported by my Catalyst 3550s, such as Private VLANs. I believe the QoS features differ on 3560 as well.

So, as I was browsing eBay (one of my favourite pastimes! :P), I found an auction for a WS-C3560-8PC-S which had been labelled “untested”. From past experiences, I have found that listings that state that they haven’t been tested are usually faulty devices, but I thought I would take the risk anyway. I was hoping it would be some small issue which I could either work around or repair, such as a bad port, or screwed up IOS image which I could just reload myself (hey! I’ve seen devices sell on eBay for pretty cheap due to non-techy people assuming it was broken because the IOS image was missing!). But I guess my luck was bad, and two days after the end of the auction, I received a large green paperweight. 🙁

After plugging the power in, the LEDs on the front of the Catalyst 3560 go on, but they just stay on in a solid state, where as they should be blinking during the boot process. I plugged the console cable in, only to find that there is no output whatsoever, not even from ROMMON, which is the first step before even loading IOS.

I have pretty little knowledge of electronics, but I did test basic things that I knew how, such as checking if the PSU was giving out the correct voltages, which it was, but that’s pretty much all I know how to check!

From my limited knowledge of electronics, I assume that something must be wrong with the Boot ROM chip since not even ROMMON is able to start. None of the parts on a Catalyst 3560 are field replicable, so I don’t think I can test any parts by switching them around either.

I am quite disappointed that this Catalyst 3560 is dead, but I tried my luck, and it turned out bad, no biggie. 🙂

Hopefully I will be able to find a Catalyst 3650 soon!

If anyone has any ideas I can try in order to fix this device, I would be quite eager to make an attempt! 🙂

Two more Cisco 7204 VXRs Added to My Home Lab!

Cisco 7204 VXRs Last week, I was browsing eBay (as you do!), and noticed two Cisco 7204 VXR routers auctions which were about to end pretty soon, price was £0.99, and there were no bids! So, I figured I would go ahead and bid. To my surprise, I won both!

I managed to win one of them for £20, and the other for £0.99! £20.99 for two 7204 VXRs isn’t bad at all, just a quick search on eBay shows that the NPE-300s, which came with both routers, is generally selling for £30, so I’m quite pleased.

The I/O controllers (C7200-I/O) are a bit old, and use DB-25 connector for the console port and not the normal RJ-45 that most Cisco devices use. The I/O controller don’t have any Ethernet ports either, but I did get some FastEthernet modules with both routers. I will probably upgrade the I/O controllers to C7200-I/O-2FE/E some time this year, but for now, it’ll do. 🙂

I now have three 7204 VXRs in my rack, the first one I bought last year some time.

In the picture:

  • Top 7204 VXR has: NPE-225, 128MB RAM, C7200-I/O, Dual FastEthernet Module and an Enhanced ATM module (ATM PA-A3).
  • Middle 7204 VXR has: NPE-300 with 256MB RAM (if I remember correctly), C7200-I/O, Single EthernetModule, and an Enhanced ATM module (ATM PA-A3).
  • Bottom 7204 VXR has: NPE-300 with 256MB RAM (if I remember correctly), C7200-I/O-2FE/E, and an Enhanced ATM module (ATM PA-A3).

I’m not really sure if the Enhanced ATM modules will be of any use to me, as I don’t think it is possible to use them back-to-back (please correct me if I am wrong!). I do want to get a few Cisco PA-4T+ 4 Port Serial modules but that’s for later on.

Cisco ASA 5505 RAM Upgrade

Edit: 3rd June 2014 – If you are reading this post, you should check out my follow up post: Cisco ASA 9.2 on Cisco ASA 5505 with Unsupported Memory Configuration Fail.

I have two Cisco ASA 5505s in my home lab which I acquired almost two years ago from eBay. I was pretty lucky, as I paid under £70 for each because the seller wasn’t too sure what they were! Looking on eBay now, they are selling for around £120! 🙂

Pretty much straight away, I wanted to upgrade to the ASA 8.3 code, which required a RAM upgrade, so I upgraded it.

Starting from ASA 8.3, the minimum required RAM needed to run 8.3 code and newer on a 5505 is 512MB. This is also the maximum officially supported amount of RAM.

Buying official Cisco RAM is, as always, quite expensive, but since the ASA 5505 uses standard DDR RAM, it is actually possible to use third-party RAM in the ASA 5505.

When I originally performed this upgrade, I found that on various forums many people had actually upgraded past the official supported amount of RAM, and upgraded their ASA 5505s to 1GB RAM.

Intrigued  by this, and due to needing the extra RAM for the 8.3 code, I decided to upgrade both my ASAs to 1GB as well!

There aren’t any ground breaking advantages to upgrading to 1GB as far as I know. I’m guessing the ASA will be able to hold a lot more entries in the NAT table, but I don’t really push my ASAs to their limits anyway.

I ended up buying two CT12864Z40B sticks from Crucial, which have worked flawlessly for the past year.

Almost 14 months later, I needed to crack open the case of the ASAs again to get to the CompactFlash. I thought I’d make a quick post about the RAM upgrade process while I’m at it.

The upgrade is very easy, anyone could do it, but I was bored, and wanted to write a blog post! 🙂

  1. Place the ASA upside down, and unscrew the three screws at the bottom.
    Cisco ASA 5505 Screws
  2. Remove the cover
    Cisco ASA 5505 Internals
  3. Take out the old RAM, and put in the new RAM.
    Cisco ASA 5505 RAM
  4. You can optionally also upgrade the CompactFlash at this time. I’m using the stock 128MB that came with the ASAs at the moment, but I will probably upgrade sometime soon. 🙂
    Cisco ASA 5505 CompactFlash
  5. Close everything up, and plug-in the power!
    Cisco ASA 5505 Failover Pair

All done! I haven’t got a screenshot of it booting at the moment, but I will probably update this post tomorrow with one.

I plan to upgrade the CompactFlash to 4GB as well so I have more working space when I am using the “packet sniffer” built into the ASA. This is a very easy process as well, but you have to be careful to copy over your licence files as well. I will be making a post about this as well when I have done the upgrade.

My Goals for 2013: CCNP and RHCE?

I’ve been thinking about renewing my RHCE for quite sometime now, and completing my CCNP but I haven’t really got around to it, mainly due to the price of the exam being a little pricey (if I remember correctly!), but also due to not having enough time.

So for this year, I wanted to set a deadline for myself to complete them. With a deadline, it is easier to visualize and plan what to study and when, and allows you see your progress better.

So, my goal is to complete CCNP ideally by the end of May, or by the end of June at the latest. I think it should be possible! There are three parts to the CCNP: ROUTE, SWITCH, and TSHOOT. If I complete one per-month, it should be achievable!

Like most people, I am using the Cisco CCNP Routing and Switching Official Certification Library books as my study material, and highly recommend them.

On that note, I have added a “Home Lab” page where you can see pretty pictures of my rack, and my “CCNP Lab”. It’s nothing close to something as awesome as Scott Morris’ Lab, but it’s coming along! 😉

I have read that RedHat will be releasing RHEL7 in the second half of this year, so it is a perfect opportunity to renew my RHCE! My goal end date will depend on when RHEL7 will be released, and when the test centers are actually testing under RHEL7.

Hopefully this will be earlier into the second half of the year, so I have plenty of time to take the exam before the end of December!

Both CCNP and RHCE are great certifications, which are very highly regarded by employers and professionals.

A lot of people seem to think they don’t go well together, as RHCE is better for System Administrators and CCNP is more for Network Administrators, but I totally disagree since I feel that the lines between sysadmins and netadmins is very quickly disappearing thanks to virtualization and “cloud” technologies.

Cisco Unified IP Phone 7912G – SIP to SCCP

As stated in my last post, I received my CCNP Lab Kit in the post last week.

In my excitement, I decided to switch my IP Phones from the SCCP firmware (which was the software originally on the phones) to the SIP firmware so that I could connect to VoIPTalk.

Now that the excitement has died down a little, I wanted to switch back to SCCP as, from what I can tell, it provides more features than SIP.

As I’m not too familiar with Cisco IP Phones, I started Googling for instructions on how to switch back, but I couldn’t really find any instructions on how to do so.

In the end I tried the same way I had originally upgraded to the SIP firmware. I edited my gkdefault.txt which originally contained the following line:
And replaced it with:


You can read what the values mean on the Cisco site, but all I had to change was two last values of the line:
0x060111a -> 0x070409a

CP7912080000SIP060111A.sbin -> CP7912080003SCCP070409A.sbin

The first value I had to change was the build ID/date, which is (from what I can tell) the last few characters in the file name after the “SIP” or “SCCP” bit.

The second value is pretty self explanatory, its just the file name of the firmware file you have.

Next, I used cfgfmt to convert the file into a .cfg file compatible with the phones, and put it on my TFTP server.

I then restarted the phones, and behold! They were downloading the SCCP firmware image. 🙂

I’m not sure if this is the “correct” way to switch back to the SCCP firmware, but it worked for me and I don’t see why it wouldn’t be correct, it seems pretty obvious. The only reason I am a little confused is the fact that while searching for instructions to switch back, I found a lot of people having difficulties switching back and even some companies offering a “recovery” service for people in this situation.

Hopefully my post will help other people who are in this situation.

Now I just need to figure out how to get the CTU ringtone onto the phone. 😀

Cisco CCNP Lab Kit

Cisco CCNA Lab Kit

UPDATE: You can see the latest pictures of my home lab on my “Home Lab” page

As I have pretty much completed my studies for the Cisco CCNA exams, I decided I would build up my lab so I could “practice” for the Cisco CCNP exams. A lot of people recommend using a simulator/emulator such as Dynamips, but I don’t think that works out to be just as good as using real hardware but that’s a different matter. 🙂

I had originally bought my CCNA Lab Kit from the nice people at ITelligentsia so I decided I would buy the rest of my equipment from them as well.

My current lab consists of the following:

  • Cisco 1800 Series : 1x Cisco 1841 (I bought this separately from someone else)
  • Cisco 2600 Series: 1x Cisco 2610, 2x Cisco 2511XM, 1x Cisck 2621XM
  • Cisco 2500 Series: 2x Cisco 2501, 1x Cisck 2509
  • Cisco 1700 Series: 1x Cisco 1721 (I bought this separately from someone else)
  • Cisco Catalyst 3550 Series: 2x WS-C3550-24 SMI
  • Cisco Catalyst 2950 Series: 3x WS-C2950-12
  • Catalyst 2900 Series XL: 2x Cisco 2924XL
  • Cisco 2000 Series Wireless LAN Controller: AIR-WLC2006-K9
  • Cisco Aironet 1200 Series: Cisco Aironet 1231 (AIR-LAP1231G-E-K9)
  • 3x Cisco Unified IP Phone 7912G

Hopefully this will be enough to allow me to get going, although I REALLY need a new rack. My 24U rack is already full, so my UPS (4U), Server (4U) and new lab equipment are sitting on the floor, and being very difficult to get access to.

Hopefully I will be able to get two from work in March as we will be moving offices, and from what I can tell, they will be getting new server racks. 🙂

I also bought a UPS a few weeks ago, but I’ve had some trouble with it. The UPS is a PowerWare 5119 RM 3000VA UPS. I have connected a few of my routers to it, and left it charging for over 24 hours, but when I kill the power the UPS goes into a strange state in which it seems to keep switching on and off and lighting up random lights on the front. From Googling a bit, I found that I might need to change some settings using the management serial port. Unfortunately, the UPS does not use a “standard” serial pin out, so I will have to build a cable when I can. Hopefully I will be able to sort the issue, otherwise I will have to send it back to the place I bought it from for repair. 🙁