Cannot Access / Open ASDM

KB ID 0000458

Problem

Out of the box Cisco PIX/ASA devices should have a working ASDM. This config can get broken over time, and also there are a few things that can trip you up on your client machine.

Solution

Make sure the client machine you are using is not the problem

1. The ASDM runs using Java make sure the machine has Java installed.

Note: If you are using Java version 7 Update 51 see the following article.

Unable to Access ASDM – “Unable to launch device manager from…”

2. Make sure the internet browser you are using is supported:

Operating System
Browser
 
Java SE Plug-in1
Internet Explorer
Firefox2
Safari
Chrome

Microsoft Windows

10
8(8.1)
7
Server 2012 R2
Server 2012
2008 Server
XP

Yes

Yes

No support

Yes

8.0

Apple Macintosh OS X:

10.6
10.5
10.4

No support

Yes

Yes

Yes (64 bit only)

8.0

Ubuntu Linux 14.04
Debian Linux 7

N/A

Yes

N/A

Yes

8.0 (Oracle only)

Note: Support for Java 5.0 was removed in ASDM 6.4. Obtain Sun Java updates from java.sun.com.

Note: ASDM requires an SSL connection from the browser to the ASA. By default, Firefox does not support base encryption (DES) for SSL and therefore requires the ASA to have a strong encryption (3DES/AES) license. As a workaround, you can enable the security.ssl3.dhe_dss_des_sha setting in Firefox. See http://kb.mozillazine.org/About:config to learn how to change hidden configuration preferences.

3. Make sure you are NOT trying to access the ASDM through a proxy server, this is a common “gotcha”!

4. Can another machine access the ASDM?

5. If the ASDM opens but does not display correctly, then do the following, File > Clear ASDM Cache > File > Clear Internal Log Buffer > File > Refresh ASDM with the running Configuration on the Device.

Make sure the ASA is configured correctly, and your PC is “allowed” access

1. Connect to the firewall using either SSH, Telnet, or via the Console Cable.

2. Log into the firewall, go to enable mode > Enter the enable password

[box]

Type help or '?' for a list of available commands.
PetesASA> enable
Password: ********
PetesASA#

[/box]

3. The ASDM is enabled with the command “http server enabled”, to make sure that’s there issue a “show run http” command”

[box]

PetesASA# show run http
http server enable
http 10.254.254.0 255.255.255.0 inside
http 123.123.123.123 255.255.255.255 outside

[/box]

Note: if the command is NOT there, you need to issue the following three commands:

[box]

PetesASA# configure terminal
PetesASA(config)# http server enable
PetesASA(config)# write mem
Building configuration...
Cryptochecksum: 9c4700fe 475d22c4 13442d06 b0317c69

9878 bytes copied in 1.550 secs (9878 bytes/sec)
[OK]
PetesASA(config)# 

[/box]

Note: If you see a number after the command e.g. “http server enable 2456” then you need to access the ASDM on that port, like so {IP address/Name of ASA}:2456 (This is common if you’re port forwarding https but you still want to access the ASDM externally).

4. Assuming that the ASDM has been enabled, the IP address you are accessing from (or the subnet you are on) also needs to be allowed access. You will notice in step 3 above that when you issue the show run http command, it also shows you the addresses that are allowed access, if yours is NOT listed you can add it as follows:

[box]

PetesASA# configure terminal
PetesASA(config)# http 10.254.254.5 255.255.255.255 inside
PetesASA(config)# http 10.254.254.0 255.255.255.0 inside
PetesASA(config)# http 123.123.123.123 255.255.255.255 outside
PetesASA(config)# write mem
Building configuration...

Cryptochecksum: 9c4700fe 475d22c4 13442d06 b0317c89 9878 bytes copied in 1.550 secs (9878 bytes/sec)
[OK]
PetesASA(config)#

[/box]

5. At this point try and access the ASDM again.

6. The ASA needs to be told what file to use for the ASDM, to make sure its been told issue the following command, (If there is NOT one specified then skip forward to step 7 to see if there is an ASDM image on the firewal)l.

[box]

PetesASA# show run asdm
asdm image disk0:/asdm-739.bin

Note: on a Cisco PIX the results will look like..

PetesPIX# show run asdm
asdm image flash:/asdm-501.bin

[/box]

7. Write down the file that it has been told to use (in the example above asdm-632.bin). Then make sure that file is actually in the firewalls memory with a “show flash” command.

[box]

PetesASA# show flash
--#-- --length-- -----date/time------ path
142 15943680 May 08 2010 18:10:42 asa831-k8.bin
144 14240396 May 08 2010 18:11:50 asdm-739.bin
3 2048 Jul 21 2009 12:04:26 log
6 2048 Apr 28 2010 15:08:32 crypto_archive
163 393828 Feb 14 2010 12:23:28 crypto_archive/crypto_arch_1.bin
164 393828 Apr 28 2010 15:08:32 crypto_archive/crypto_arch_2.bin
147 9526560 Jul 21 2009 12:04:52 csd_3.4.1108.pkg
148 2048 Jul 21 2009 12:04:54 sdesktop
150 2648712 Jul 21 2009 12:04:54 anyconnect-win-2.3.0254-k9.pkg


127135744 bytes total (29583360 bytes free)

[/box]

Note: If the file you are looking for is NOT there then (providing you have a valid support agreement with Cisco) download an ASDM image and load it into the firewall see here for instructions.

Note: If the file is in the flash memory but was not referenced in step 6 then you can add the reference with the following command (obviously change the filename to match the one that’s listed in your flash memory).

[box]

PetesASA# configure terminal
PetesASA(config)# asdm image disk0:/asdm-631.bin
PetesASA(config)# write mem
Building configuration...
Cryptochecksum: 9c4700fe 475d22c4 13442d06 b0317c89

9878 bytes copied in 1.550 secs (9878 bytes/sec)
[OK]
PetesASA(config)#

[/box]

 

Related Articles, References, Credits, or External Links

Connecting to and Managing Cisco Firewalls

Cisco Allowing Remote Management

Cisco ASA5500 Update System and ASDM (From ASDM)

Juniper SRX Firewall – Allow Web Management from Outside

KB ID 0000708 

Problem

Assuming you already have web management enabled, and you want to access it from the outside (the untrusted zone).

Solution

1. Log into the web console of the Juniper.

2. Navigate to Security > Zones/Screen > Select the ‘Untrust’ Zone > Edit > Host inbound traffic – Interface > Select the Outside interface > Under Interface services add in ‘http’ > OK.

3. Then to save the change click Action > Commit.

4. Test Externally.

Related Articles, References, Credits, or External Links

NA

 

Connecting to and Configuring Cisco Routers with ‘Cisco Configuration Professional’

KB ID 0000512 

Problem

It’s not often I work on Cisco routers, but as I tend to do most of the Cisco ASA Firewalls, I’m the unofficial “Cisco Guy”. Which is fine until someone wants a router or some complex switching, then I need to do some heavy duty frowning.

Last time I put in a Cisco router it was a baby Cisco 800 series (an 877W) so I assumed the 1921 ISR router I had to put in would be the same. Before I used the Cisco SDM console that’s now either depreciated or not used, and a quick look in the flash memory of the router told me there was nothing in there apart from the IOS.

Now for all your web based router needs, you use the “Cisco Configuration Professional” software, it comes in two flavours:

1. Express – this installs on the router itself and is a cut down version.

2. PC Version – the full suite of tools installs on a Windows PC (that has Java installed) Note: is does NOT need anything else installing on the router.

To download the software you will need a valid Cisco CCO login and a valid support contract (or SmartNet) for your router. (download link).

Solution

1. Using the console cable provided with your router connect a PC/Laptop to the router and access using Hyperterminal or PuTTy, (See here for details).

2. Connect an ethernet port to your LAN, we are going to configure it to get an IP from DHCP (assuming you have DHCP of course if not give is a static IP address).

3. While connected via console cable, go to enable mode, set the ether net port you connected to DHCP, then configure Telnet and SSH login, and finally allow HTTP access.

Note: If you get an error message like “IP address may not be configured on L2 Links” then assign the IP address to the VLAN (usually, but not always VLAN 1).This is seen on smaller 800 series routers, to resolve also make sure the Ethernet port is NOT shutdown like this;

[box]

interface FastEthernet0
! <<<<<<<Note: Make sure the Ethernet ports you will use are NOT in a shutdown state!
interface FastEthernet1
shutdown
!
interface FastEthernet2
shutdown
!
interface FastEthernet3
shutdown
!
interface Vlan1
ip address 192168.1..1 255.255.255.0 <<<Or use DHCP as appropriate

[/box]

4. So all being well, this is what you should see if you issue a “show run” command.

5. Lets make sure it got an IP address with “show ip interface”.

6. Install CCP on you PC and launch it > Select “Manage Devices” > Enter the IP, username and password you set earlier > OK.

7. If discovery fails make sure you’re cabled correctly and select “Discover”.

8. It connects over https so it’s normal to see this, just click yes.

9. You can now configure the router as required.

10. If you have the Security/Firewall IOS you can also manage that from here.

 

Related Articles, References, Credits, or External Links

Original Article Written 26/09/11