Cisco Firewall :: Add IP Address For SMTP Services ASA 5510
Nov 28, 2012
We have hosted spam filter service with 3rd party vendor. My vendor is switching to different spamming services and I need to add ip address lets say 44.33.454.32 to the list of allowed system that can connect to my smtp service. I am going over my firewall 5510 configs and I think I need add the entry like this: “access-list outside-to-inside extended permit tcp object-group obj-44.33.454.32 interface outside eq smtp”. [code]
I have a ASA 5510 (ver 8.4) and I have been all over the support sites looking for what I am doing wrong. I have a sanitized cut n paste of the OBJECT, NAT, ACCESS-LIST and Packet Tracer output and it keeps failing on the NAT with a rpf-check. Once i get the SMTP flowing I have to open up HTTP and HTTPS to one of the servers also.
Here it is:
RVGW# sh run object object network WiFi subnet 172.17.100.0 255.255.255.0
I'm trying to configure a simple ACL to block smtp traffic from leaving my LAN -- basically prevent internal users from setting up internet email accounts in their email clients and sending through that smtp server. i want my Exchange server only to send smtp traffic. here's what i have:
-access-list 102 extended permit tcp host 10.10.1.29 eq smtp any eq smtp <===10.10.1.29 is Exchange
-access-list 102 extended deny tcp any eq smtp any eq smtp
-access-list 102 extended permit ip any any
-access-group 102 in interface inside
after i apply this ACL to the ASA, i am still able to send from my internet email address setup in Outlook using my "foreign" smtp server.
I have an issue with my mail server(SME Server) which is behind a Cisco ASA 5500(firewall) problem is that if one leaves my network they can receive but can not send email via my SMTP also internal people can only send if they use the IP address of the server rather than the domain [URL]
We have a 5510 (8.2) with the following 4 interfaces (security-levels) inside (95), outside(0), dmz(25), and test (95). The dmz network is 10.10.10.0/24 and the outside interface is 40.133.84.69.We have run into a situation where a dmz hosted iRedMail server running postfix (10.10.10.51) is relaying mail which in some cases points back to us at 40.133.84.69 and into our Exchange server. In these cases in the dmz server's mail logs we see postfix timeout trying to connect to smtp at 40.133.84.69. When I try to telnet from 10.10.10.51 to the outside interface on port 25 it times out.We've tried different ways to allow the outside adapter to permit smtp (or any service!) from 10.10.10.51 but we're left scratching out heads.
how to go about setting up the ASA to block any SMTP traffic outbound except for our Exchange Server. This is in relationship to a SpamBot issue that blacklisted us. I have an ASA 5510 running version 6.2(5) / 8.2(2) with three ports. DMZ, Inside and the Outside interface. Up till today, I only needed to block outside traffic to our internal network which I used the ASDM to configure a rule on the outside interface for an incoming rule. I am assuming I need to create an outgoing rule on the outside interface; however, just to make sure I understand the terminology/traffic flow, I created the rule with my computer as the source (192.168.0.131) with ALL destination and the service as HTTP. My logic, which seems to fail here, is that any traffic from my computer going outbound would be blocked; however I am still able to browse... That said, if I were to change the source as the Exchange server and the Service Type to SMTP, it would not actually block traffic and therefore not solve our problem. I even gone as far as permitting traffic from my computer, expanding the hit counter and I see no hits. So I am no doubt doing this wrong. What I do know, is when I first created the rule, a second rule was automatically created (Implicit rule) that deny all sources and blocked all HTTP traffic until I changed it to Permit?
A recently added outbound rule has left my SMTP communications broken. I have since removed the rule, and had Cisco do some damage control, but it's still dropping some of the SMTP traffic. I get a number of NDR messages each day like the one below:Your message did not reach some or all of the intended recipients. Subject: RE: Christopher, Curt Sent: 8/19/2011 9:38 AM The following recipient(s) could not be reached:
[URL] on 8/21/2011 9:49 AM Could not deliver the message in the time limit specified. Please retry or contact your administrator. <630.SM.Local #4.4.7>
Your message did not reach some or all of the intended recipients. Subject: RE: Christopher Curd Sent: 8/19/2011 9:38 AM The following recipient(s) could not be reached: JWillar@email.com on 8/21/2011 9:49 AM Could not deliver the message in the time limit specified. Please retry or contact your administrator. <630.SM.Local #4.4.7>
I've attached an image of my configuration (ASDM GUI). The part of the image highlighted in green are the SMTP rules. The part highlighted in yellow is another rule that I added about a month ago to block a SYN attack. This rule may be part of the problem because of the order it is in the list. Not sure, though.
I have had two Cisco techs Putty into my ASA to check things out. I think they've done all they can. I wonder at this point if it be wise to just reload the last good running-config I have prior to the Outbound rule being added.
I have an ASA 5510, one public IP address on my outside interface, an internal email server and a private network.I would like...
1: Users on my private network to be able to access the internet (PAT them to external outside address) 2: Email to be delivered to my MX (my single public IP address translated back to my internal email server.
i.e. can I share my single public IP address to serve translation in both directions (private users surfing the Internet (in-to-out) and an outside to inside NAT for email) ?
Email (MX) = 1.2.3.4 Public (outside) address = 1.2.3.4 Email server internal = 10.1.2.3 Internal private subnet for users = 10.0.0.0/8
We have configured ASA 5510. We have configure Ethernet 0/0 ( Outside ) connected with ADSL line and Ethernet 0/1 ( Inside ) Local LAN. we have configured NAT and all the traffic is passing through outside interface. Now we have connected ethernet 0/3 ( leasedline ) interface with static public IP. Now we want to allow SMTP traffic to pass through from this interface.
How to configure it if we want our local lan SMTP traffic sending through new leased line ( Static Public IP ).
I have created Different extended access-list which allow/block some specific services like IP,TCP,UDP ,ICMP etc for certain source and destination . But now I have to allow/Block all/any type of services to a certain host from a extended access-list . How can I do it ?
I've got some problem with my Mail Server since I've migrated to an ASA5510.Actually the server is in a DMZ with a private Ip ( 10.x.x.2) and it is translated to a Public IP ( 194.x.x.65).I use these configuration :
We have an ASA5510 running version 8.25. This is in our central office in London. The London network has an ip address range of 10.110.128.0/22. Connected to this via a site-to-site VPN we have a satellite office that has an IP address range of 172.16.148.0/22.
We have now connected to our parent company via another site-to-site VPN connected to the same ASA5510. Their network has an internal range of 10.110.18.0/24. It was our parent company that issued us with our range of addresses a long while ago so that it all fits in with the rest of the company.
We have resources (web servers) on their network that we use which work just as it all should. We now want to allow our satellite office to view those same web servers. The problem is that only 10.110 addresses can flow to our parent company.
I have configured the firewall at our central office and our satellite office to route across to our parent company via our network network and the packets are flowing just fine except that obviously once they reach our firewall they cannot go to our parent company because the 172.16.148 range cannot be routed there.
My idea is to NAT traffic from our satellite office to one of our local addresses before it goes over to our parent company network.
For example: If someone in our satellite office with an IP address of 172.16.150.5 attempts to request a resource from 10.110.18.12 then the request would go via the VPN to our firewall and then get NATed to 10.110.131.200 before being passed on to our parent company network.
My question is what would the NAT configuration be to achieve this. I just cannot work out what type of NAT I would need or how to construct the command. It's probably PAT as it will be multiple addresses to a single address. Essentialy, all traffic from 172.16.148.0/22 destined for 10.110.18.0/24 should get NATed at our firewall to 10.110.131.200 before being passed on.
Just to add, we already have this working from our Cisco 3000 Concentrator which is now going to be phased out hence trying to get this to work on our ASA. The satellite office has now been moved to the ASA and as of today our parent company has been moved to the ASA.
I am using an ASA 5510 firewall in routed mode.How can I filter incoming traffic by mac address on the AS 5510 ? I have already setup a static access rule for rdp users on the outside to access a terminal server on the inside.Now, i would like to further limit access from specific computers only.
I added a new server and created a new static NAT assignment on the ASA 5510 to the server's IP. When I browse to the web to check what public IP it's reporting, it shows the wrong IP. I disabled the network interface on the server, ran "clear xslate", reenabled the network interface, ran "sho xlate" and while the correct translation was in the table, the server still reported the wrong IP address.I even ran a packet trace and it showed the IP address being correctly translated to the proper public IP, but when I browse to the web I get the same erroneous public IP. [code]
I have just started to use an ASA 5510 for my network. I use the DHCP server on it and after i made the change over to ASA hosts started loosing their IP address. This was not a problem before on my old firewall that aso had the roll of DHCP.
Is it possible that something is wrongly sett on the asa? All traffic is flowing normaly when this does not happen.
Information: Lease length: 172800 address pool: 134 addresses hosts: around 45 + mobile units 45
We had a problem with SMTP inspection dropping some regular emails (Cisco 2901 IOS 15.0).Incoming mails are going thru Spam and Virus Blocker so that bypassing SMTP inspection is not security issue in this case.
IOS Firewall (ZBF) Limit SMTP connections from same IP
we are running a Postfix MTA behind a IOS Firewall (ZBF) on a CISCO1921. Sometimes we get more than 2000 smtp login attemps like
postfix/smtpd[123456]: connect from (...) (...) postfix/smtpd[123456]: lost connection after AUTH from (...)
in one second. May be bruteforce or DoS ... nevertheless - we like to protect the Postfix MTA from this stuff.
Can we inspect the smtp and limit connections in a time period from the the same IP? Something like "not more than 10 smtp connections during 60 seconds from the same ip" .
Is it possible to perform static Nat's through an internal network?I have a ASA 5510 with a public outside interface (let’s call it 68.68.68.1), and I have an inside private IP address (192.168.1.2/24). The inside IP address leads to a 4900m with that interface being configured with a 192.168.1.1 (no switching). On the 4900 M I have several VLANs one of them is an internal DMZ of sorts. (192.168.2.0/24). Within this DMZ network are several Web servers which need to be associated a public IP address (68.68.68.x).
Every time I configure a static Nat to associating a public IP address with an internal IP address within the DMZ, packet Tracer on the ASA informs me that the packet gets dropped at the static Nat and I cannot figure out why this is so.Safe it to say my question still stands is it possible to Nat (68.68.68.222 to and 92.168.2.60) given the configuration above, and how would I go about configuring in such the manner above so that I acn apply static nat through the 192.168.1.0 network to reach the 192.168.2.0 network.
We have an ASA 5510 and we also have two separate address pools which have been provided by our ISP. The addresses are not contiguous. Is there a way to configure an interface on the ASA to handle both sets of public address pools? If the outside interface is set up on eth0/0 would I create two subinterfaces (eth0/0.1, eth0/0.2) and assign each subinterface an address pool? Then just NAT/PAT to my heart's content? At that point I would want both to route to our inside network. So it's basically two inbound sets of IP addresses comming into one interface and then comming into the network... Right now the outside interface is configured with our first set of IP addresses. We wanted additional addresses and when we called our ISP they told us we already had them - just a different pool. Hence the question. I'm guessing that I wouldn't put anything specific on the outside interface and I would put the specifics on the subinterfaces?
Will I break anything if I create a second IP address on the physical external interface of our ASA 5510? I want to point it nowhere internally but want an active interface that can be vulnerability scanned but won't lead anywhere internally.
We've had issues with our Exchange 2010 server (running on ESXi 4.1) since its default gateway was changed to our new ASA 5510. They manifested as frequent Outlook client connection dropouts or as IP address conflicts whenever Exchange was rebooted. The temporary fix was to disable the Exchange server NIC, bounce the ASA and enable the server's NIC again. We saw poor performance from Exchange after a while again, but after some research and testing I realised that disabling proxyarp on the inside interface fixed the problem permanently.
However I've now realised that the client VPN no longer routes properly because proxyarp is disabled on the inside interface, so I still have a problem.
Using Cisco ASA5510 Security Plus (Post May 2010) with 8.2(1)
I was trying to limit the number of internet IP Address that can initiate Remote Access VPN connection to the firewall. I have plan to only allow internet IP Address from few ISPs for control.
However, blocking AHP, ESP, ISAKMP, NON500-ISAKMP, and IPSec Over TCP Port Assigned in the firewall outside interface doesn't work. But it works by putting the ACL in the router before the firewall. It seems that the firewall have a "hidden" process VPN first before user entered ACL (or explicit rule), similar to Checkpoint FW's implied rule. How to get around it?
We will be moving to a new data center in the very near future and with them our WAN IP addresses will be changing. Any best course of action for changing the IP addresses throughout the firewall configuration? Would it be possible/suggested to export the running-config, make the neccessary changes, then import the config? I am familiar with the ASA 5510 only so far as changes are required. It is not something I work with on a regular basis.
I have an ASA 5510 running version 7.0. I have a problem with an exchange server using a static map and its outbounc connectivity. It connects outbound through the global address even though inbound connectivity works fine through the static mapping. The recent changes are changing of the zero route through a different interface (there are to circuit connected to this ASA on different interfaces). So the idea was to get all workstations in the office using the global address and routing out through one circuit, and the servers connecting in/out through the other circuit. Shouldn't a static mapping ignore what the zero route is?
Here are what I believe to be the relevant configs.
interface Ethernet0/0 description New 6mb circuit speed 100
[Code]....
So exchang2 server can be connected to from the outside properly via IP xxx.207.51.231/exchange2-outside, but all outbound connections from this server are going out via IP xxx.122.47.218/circuit-6mb as do all the workstations due to the global address statement.
I have two CSS 11500 series.In just a few months i will have ready a DRS (Disaster Recovery Site), where i will have 2 more servers to add to the environment.
i'm using some catalysts 3560 with 10 VLANs and inter vlan routing. we use a windows deployment services server to install our workstations. the pxe boot works fine. the image is loading, and when the windows 7 PE is booting, the dhcp request failes. when i use a small not manageable switch between the computers and the catalysts, it works fine.all other things work fine.
I have an ASA 5500 Firewall. I need to figure out how to log all events using Port 25 to determine if there are any rogue devices on our network. I was trying to figure out how to do this via the Real-Time Monitoring (filter) but have had no success.
Most examples of NAT translation using an ASA 8.4 are based on servers within a DMZ. In my case it's not because the mailserver also functions as an data and Active Directory server for my local domain. If tried to config the ASA for a while now and throw it in the corner for a couple of months out of frustration. Now I got some time left during christmas break I decided to start again.My purpose is to NAT SMTP / POP traffic from the internet, trough the ASA to my (inside) server. This is what I got so far. With this config I'm unable to telnet the inside server (192.168.1.10) from a remote location.
I can ping 192.168.1.10 from the ASA CLI. I can Ping DNS 4.2.2.2 from the CLI (internet access). I can Telnet the server from the inside LAN, using: telnet 192.168.1.10 25.But I can't Telnet from an outside location using: Telnet 95.*.*.218 25 Because my server is on the Inside interface (diffenrent subnet) do I need an additional route?
Below is the interesting part of my config. I have static NAT configured and working inbound for the Exchange Server and the Barracuda, however outbound traffic from those hosts comes out as the interface IP. Thoughts? I've tried a number of things (outside, inside), etc.