2 IOS Firewall interface

Similar Questions

• Deployment IOS firewall feature set

  Hi all

  We strive to deploy the 2811 router firewalls with version 2.5 of SDM. We chose basic firewall configuration option. It has forced us to choose the approved and unapproved interfaces and we did the same. She said entering the trust interface access list and inspect the ip on the interface of the United Nations-trusetd command.

  Also, initially, we want to allow all traffic not reliable interface for the trust interface, so we manually ban ip allowed everything inside the network block? - is - right?

  We have another question, we would be having another interface on the router to connect to a different network and preference is not to configure this interface as approved or not approved, in this scenario, if all traffic from undefined interface can access the interface of confidence or also not approved interface?

  Any help would be really appreciated

  Thank you

  Concerning

  Anantha Subramanian Natarajan

  Hello André,

  "In addition, initially we want to allow all traffic to untrusted interface" which would completely break the idea of the deployment of the IOS Firewall. Nature of the statefull firewall that comes with the firewall option IOS is to block all traffic from an untrusted by default interface, then only allow the return circulation of connections, initiated from a reliable interface (inspection). And you can also allow a portion of the traffic you trust manually.

  "We have another question, we would be having another interface on the router to connect to a different network and preferably does not configure this interface as approved or not approved, in this scenario, if all traffic from undefined interface will be able to access the interface of confidence or also not approved interface?

  If the inspection rule is applied in the direction of untrusted interface oubound, do not hesitate to unplugged other interfaces as being approved.

  Concerning

• 1721 router + 4esw, WIC + IOS firewall

  Hello

  I have a router (192.168.157.254) Cisco 1721 with a 4port10/100 wic installed.

  Is it possible to filter using IOS Firewall if wic address and lan are similar? I know it's that they have different ip addresses is possible, but if they are in the same LAN?

  For example:

  A server (192.168.157.10) connected directly to the router FILTER wic and using the LAN interface.

  Is possible?

  Best regards

  Yes, the IOS Firewall can filter even if the address LAN and wic are similar. The following link can help you

  http://www.Cisco.com/en/us/docs/iOS/12_4/secure/configuration/guide/schfirwl.html

• IOS Firewall

  Hello

  What devices can I find ios firewall services, ZBF and url filtering? is it only the routers or there are PIX too?

  Thank you

  PIX and ASA devices support ZBF, URL filtering and firewall services. However almost all high mid-range to routers have firewall/ios function (Cisco3640 router with firewall IOS version 12.2 media services), SRI series routers support ZBF and URL filtering.

• Multi-tenant IOS Firewall and security even subinterfaces 9.0

  Hi all

  I'm so used to< 8.3="" and="" am="" having="" great="" difficulty="" getting="" an="" environment="" working="" properly="" so="" i'm="" now="" going="" to="" leverage="" the="" cisco="">

  We set up a network with clients behind a pair of 5510 s.  All of these clients will have their own dedicated sous-interface in their own VLAN.  Out the door, I got inter - allowed security-same interface and all networks communicate with each other.  I certainly don't want that, so I have disabled this command and now each network client is unable to communicate with each other, as expected.

  The problem now lies in networks where a customer have 2 VLANS separated (say a staging and a prod environment) where they need to communicate.  Is it feasible if they are of the same security level and even security allowed inter-interface is disabled?  I just need to create an ACL for the networks to talk?  Is there a better way to do this with the same security allowed active inter-interface?

  8.3 pre, I have same security allowed active inter-interface, but traffic could not speak to the other interface unless I created an exemption NAT and ACLs.  Always create a NAT exemption?

  Hello

  The basic problem that you run with different software levels is the parameter 'nat-control' that exists in 8.2 (or earlier version), but does not exist in version 8.3 (or subsequent version of the Software ASA).

  In the 8.2 and pre software you got with the nat configuration change 'control' of requiring a connection to have a NAT configuration to be able to pass traffic through the ASA. Of course this coupled with the 'security level' gave you more changes to control traffic without resorting to the ACL.

  However, in the new software of 8.3 and later the "nat-control" level no longer exists and that a connection has a NAT configuration that be applied or not ASA still allows the connection (subject other ASA controls allow) so basically you won't need NAT configurations between your local interface. The most common NAT configurations should be between your local interface and the "external" ASA interface.

  If you try to control traffic between interfaces with the global configuration commands you mention, you will eventually be 'juggling' with the 'security level' configurations autour constantly so that the correct rules for traffic is applied.

  This question came up on these forums every now and then, and I almost always offer the same approach which is to set up an ACL on EACH interface of the ASA.

  • Remember to leave the 'same-security-traffic"on the SAA configurations. It is because even if you have interface ACL allowing traffic, if they are for some reason any left with identical "security level"custom ACL be sufficient to allow the traffic. "
  • Configure each interface an ACL
  • Initially to configure the ACL to create a "object-group" that will contain EACH network behind your local interface of firewall (except the "outside" ofcourse)
  • Use this category 'object' at THE start of ACL interface to BLOCK ALL traffic behind this interface to these networks
  • After that allow or block different/Out Internet - linked as usual traffic
  • In the same networks 2 (or more) behind the need of different interfaces to communicate with each other, set up a statement that allows early each ACL. The already existing 'decline' exposed with the 'object' group already will ensure that other traffic between networks are blocked

  A very simple example, you might want to consider the following

  Networks:

  • LAN1: 10.10.10.0/24
  • LAN2: 10.10.20.0/24
  • DMZ1: 192.168.100.0/24
  • DMZ2: 192.168.200.0/24

  permit same-security-traffic inter-interface

  Interface GigabitEthernet0/0

  Description box

  interface GigabitEthernet0/0.10

  VLAN 10

  nameif LAN1

  security-level 100

  IP 10.10.10.1 255.255.255.0

  interface GigabitEthernet0/0.20

  VLAN 20

  nameif LAN2

  security-level 100

  IP 10.10.20.1 255.255.255.0

  interface GigabitEthernet0/0.100

  VLAN 100

  nameif DMZ1

  security-level 100

  IP 192.168.100.1 address 255.255.255.0

  interface GigabitEthernet0/0,200

  VLAN 200

  nameif DMZ2

  security-level 100

  192.168.200.1 IP address 255.255.255.0

  object-group network BLOCK-LOCAL-NETWORKS

  object-network 10.10.10.0 255.255.255.0

  object-network 10.10.20.0 255.255.255.0

  object-network 192.168.10.0 255.255.255.0

  object-network 192.168.20.0 255.255.255.0

  access-list LAN1 - IN note allow HTTP / HTTPS in the DMZ1 Server

  access-list LAN1 - permit tcp 10.10.10.0 255.255.0 host 192.168.100.100 eq www

  access-list LAN1 - permit tcp 10.10.10.0 255.255.0 host 192.168.100.100 eq https

  LAN1-IN access-list note block traffic to another local network

  access-list LAN1 - deny ip any object-group NETWORK-LOCAL-BLOCK

  Note LAN1-IN access list allows any outbound

  access-list IN LAN1 ip 10.10.10.0 allow 255.255.255.0 any

  LAN1-IN group access to the LAN1 interface

  And of course all other ACL would follow the same model in one form or another. You would really have to worry about traffic is allowed between interfaces, but rather the most work would probably add "allowed" in the upper part of each ACL when required for communication inter-interface. But I guess that the amount of these additions would remain also to a manageable level for FW admins.

  Naturally in environments the biggest you would probably get a high-end ASA and virtualize it and separate each customer environment in their own security context where you would avoid this situation together. Naturally the biggest points against this solution usually can be fresh and the fact that virtualize the ASA multiple context mode disables some essential operational capability of the SAA, which the most important is probably the Client VPN connections (VPN L2L is supported in the software in multiple context Mode 9.x)

  Hope this helps

  Don't forget to mark the reply as the answer if it answered your question. And/or useful response rates

  Request more if needed

  -Jouni

• Even IOS VPN Interface Internet Access issue

  Hi all

  I was wondering if there was any equivalent to these orders of ASA 5510 to put on a cisco IOS router 2811.

  Split-tunnel-policy excludespecified

  value of Split-tunnel-network-list LOCAL_LAN_ACCESS

  What I want to achieve is to give internet access to my vpn users without creating a split tunnel, which means the vpn user turns off the Internet on the same interface on that their vpn router ends.

  Is a 2811 for this there docs? I could not find the doc for it...

  TIA,

  -Fred

  Try this link

  Public Internet on a stick

  http://www.Cisco.com/en/us/products/sw/secursw/ps2308/products_configuration_example09186a008073b06b.shtml#intro

  Rgds

  Jorge

• IOS Tunnel interface. Size of the NEGATIVE queue?

  When I do a 'show int' on my tunnel interface, I see a NEGATIVE queue size. Is it normal or I see a bug in the IOS?

  Router #sho int tunnel1

  Tunnel1 is up, line protocol is up

  Material is Tunnel

  The Internet address is 172.16.14.2/30

  MTU 1514 bytes, BW 600 Kbit, DLY 500000 usec,

  reliability 255/255, txload 1/255, rxload 1/255

  Encapsulation TUNNEL, loopback not set

  KeepAlive not set

  Source xxx.xx.xxx.xx (FastEthernet4), destination yyy.yyy.yy.yy tunnel

  Tunnel protocol / transport GRE/IP, off key, off sequencing

  TTL 255 tunnel

  Disabled packages, quick tunneling active parity check

  Tunnel of transmission bandwidth 8000 (Kbps)

  Tunnel to receive 8000 (Kbps) bandwidth

  Last entry of 00:00:00, 00:00:00 exit, exit hang never

  Final cleaning of "show interface" counters 00:15:14

  Queue entry :-542544/75/0/0 (size/max/drops/dumps); Total output drops: 0

  Strategy of queues: fifo (pre-ranking QOS)

  Output queue: 0/0 (size/max)

  5 minute input rate 0 bps, 0 packets/s

  5 minute output rate 0 bps, 0 packets/s

  packages of 1499, 148506 bytes, 0 no buffer entry

  Received 0 broadcasts, 0 Runts, 0 Giants 0 shifters

  errors entry 0, 0 CRC, overgrown plot of 0, 0, 0 ignored, 0 abort

  My config tunnel isn't something special...

  Tunnel1 interface

  bandwidth 600

  IP 172.16.14.2 255.255.255.252

  IP 1400 MTU

  IP pim sparse - dense mode

  QoS before filing

  source of tunnel FastEthernet4

  destination yyy.yyy.yy.yyy tunnel

  Looks like a software defect. The closest I could find is Bug ID CSCed86842.

  http://www.Cisco.com/cgi-bin/support/Bugtool/onebug.pl?BugID=CSCed86842&SUBM

  I hope it helps.

  Kind regards

  Arul

• IOS Firewall between network internal

  Does anyone have an example of configuration or a guideline for the implementation of a standard firewall between a group internal?

  The scenario is a 3640, with only 2 network interfaces to provide a firewall for a small network with only 3 customers on this subject who need access to internal LAN of business for an application only.

  I have loads of info on all other types of scenario, but not one like this where no internet access is required or used and 2 networks are connected by frame relay or ISDN.

  Any help would be greatly appreciated.

  Claiming that only TCP applications are used and a specific web server. In addition, this example assumes that the 3640 is at the remote site. If the other access is desired you will need to check other protocols. Don't forget that you will need directions on the local and remote router to the appropriate subnets. For security, it would also make sense to limit

  inspect the name fw tcp IP

  interface ethernet0/0

  customer group-access IP in

  interface serial0/0

  IP inspect fw in

  customer IP extended access list

  allow any host 192.168.1.2 eq 80

• IOS firewall/Internet on DSL (PPPoE)

  I have a Cisco 2651XM laying around and I want to implement a NAT (inside) firewall and the external interface to dial a number using PPPoE (it would be connected to t a DSL modem). How can I do this?

  Thank you!

  Also, make sure that your user name and the password that you use for pap authentication are correct. It won't hurt delete this statement and configure it again just to make sure that you did not a character during the first extra space that you inadvertently configured.

• Configuration of the PIX firewall Interface

  Hello

  On a PIX 525 running ver 6.3 4 port 10/100 card installed it will be possible to configure interfaces as follows:

  E0 - inside interface

  E1 - failover stateful Firewall

  E2 - Firewall failover monitoring link

  E5 - outside interface

  I'm basically is unsure as to if it is possible to move the external interface to its default configuration as e0 to E5, and even if it will be possible to specify e0 as the interface instead of the default E1 confiuration inside = inside.

  Another quickie - I guess that with the additional 4 port 10/100 card installed my interfaces will be numbered e0 - e5. Is this correct?

  Thank you.

  Said Cisco documentation is not possible to change the name and the security level of inside interface, but I experience it is possible:

  nameif ethernet1 failover security50

  nameif ethernet5 off security0

  etc...

  I would not recommend doing in a production environment because it would create a lot of confusion...

  525 has two fixed interfaces e0 e1 - card expansion port 4 should therefore be numbered e2, e3 (from left to right)

  M.

  Hope that helps the rate if it isn't

• Levels of security ASA Firewall interface and access lists

  Hello

  I am trying to understand the correlation between the ACL and the levels of security on an ASA of the interface.

  I work with an ASA using both! ??

  Is this possible?

  Assumptions: Any ACL applied below is on the wire of transmission (interface) only in the inbound direction.

  Scenario 1

  interface level high security to security level low interface.

  No ACLs = passes as I hope

  What happens if there is an ACL refusing a test package in the above scenario?

  Scenario 2

  Low security to high

  No traffic = ACL will not pass as I hope

  What happens if there is an ACL that allows the trial above package.

  I have trawled through documentation on the web site and cannot find examples, including the two (using ACL in conjunction with security levels).

  Thank you in advance for any help offered.

  Levels of security on the interfaces on the SAA are to define how much you agree with the traffic from this interface.  Level 100 is the most reliable and 0 is least reliable.  Some people will use a DMZ 50 because trust you him so of internet traffic, but less traffic then internal.

  That's how I look at the levels of security:

  A security level of 1 to 99 always two implicit ACL.  To allow traffic down interfaces of security and the right to refuse traffic toward higher level security interfaces.  100 has a security level IP implicitly allowed a full and level 0 has implicit deny ip any one.

  In scenario 1, if you apply an ACL to deny a security level of 1-99, it will eliminate implicit permit than an entire intellectual property and deny traffic based on the ACL and all traffic.  You create an ACL to allow some other desired traffic.  If this ACL is applied to a security level of 100, he'll refuse essentially all traffic because it will remove the authorization implicit ip any any ACL.  Once again, you will need to create an another ACL to allow traffic.

  In scenario 2, if you apply a permit ACL to an interface of level 0 of security, it will allow that traffic, but continue to deny all other traffic.  However, if the security level is 1-100, it will be all traffic to that destination and remove the implicit ACL (permit and deny)

• IOS Firewall feature set and slow down access HTTP...

  Recently turned on the firewall, on a router, and often feature some

  Web sites are rather slow. I tweaked the ip inspect max-incomplete and

  one - minutes, but the problem persists - deletion of IP inspect and these

  command solves the problem.

  ANY ideas on how to fix?

  Sincerely,

  Daniel Melameth

  You inspect http traffic in particular? If Yes, I would like to remove this and just inspect other protocols and tcp and udp in general. Inspection of http is really useful if you want to stop the Java applets arrive, which to be honest, that almost person does. If you do not have something like this, remove the inspection of http as it slow down considerably.

  That said, 12.2 (8) T has had a lot of performance improvements put into it for the CBAC specifically, you can also try the upgrade than or later to see if it solves the problem also. See http://www.cisco.com/univercd/cc/td/doc/product/software/ios122/122newft/122t/122t8/ftfirewl.htm

• IOS Firewall (CBAC) + Path MTU Discovery

  I was reading just through the 12.2 T documentation CBAC and saw the section on the icmp inspection and how he wildcards outside IP because no matter what a leap could return it with the responses of time exceeded and inaccessible destination.

  See that made me wonder if this was true for TCP as well, especially in situations that involve Path MTU Discovery. If an internal system initiates an outgoing TCP connection that is inspected by the FW IOS, an external host responds with an ICMP Fragmentation needed but DF Bit set to message, the router will consider this part of the session and send it to the host internal?

  Thanks in advance.

  -Mason

  Mason,

  ICMP by CBAC inspection does not include packets 'package-too-great. Therefore, you must explicitly allow these packages in your ACL for PMTUD to work that the router would not consider these packages to be part of the TCP session and drop them.

  See the link below for the types of ICMP packets supported by CBAC.

  http://www.Cisco.com/en/us/products/ps6350/products_configuration_guide_chapter09186a0080455b0d.html

  HTH,

  Sundar

• Toggle the navigation on iOS user interface 9

  All,

  I'm having a problem with iOS 9 gel whenever I run the DPS Nav toggle function.

  This happens on the examples of gesture of Adobe which was provided as well as my html page; both of which work well on iOS 8.

  onClick = "adobeDPS.Gesture.toggleNavigationUI ()" "

  is this a known issue?

  Yes, it is a known issue that we expect to be addressed in a few weeks with the next update.

• Using Cisco IOS Firewall VPN clinet

  Hello

  I configured RTR1 to support VPN Clients. RTR1 has a site 2 RTR 2 site VPN tunnel.

  Customer VPN connected to RTR1 have RTR1 LAN IP connectivity. How can I get the VPN Client LAN to access the local network RTR2?

  I've included the VPN Client LAN to be ecrypted in the VPN tunnel to the LAN RTR2 and Vice Versa. I also tried a static router configured on RTR2 for the LAN of Client VPN IP WAN RTR1 serving of next hop.

  Still doesn't work is not for me. Any ideas?

  Thank you

  The other side added your remote VPN client pool to its configuration? The remote site must know its interesting traffic as well. Is RTR2 NAT'ing? Cleaned the configs for the two routers would help a lot.