I have a strange problem which looks to me like a DOS attack from the inside..but I cant be sure.
Symptoms:
All xlate connections used within hours.
Xlate connections start with all our servers across our WAN before moving onto all workstations.
No viruses have been found.
Looked in syslog and I cant find one single outside IP that seems to be a possible source.
I have the ASA5520, everyday I have a lot of connections through my ASA5520. But buffer in ASA5520 to save connections is limited. Now, I want my ASA can auto save the conn detail and Xlate to my Syslog server, how can i do that?
View 3 Replies View Relateda few weeks ago I started hosting a server for a game from my computer. It's been working fine and I've been having no problems except for one.After a few hours of hosting my server, my internet connection will immediately drop down to 1.0mbps, and I lose all connection to everything until I reboot my computer.I'm using a wireless internet adapter right now and having this problem, but when I used a wired connection a similar thing would happen where my entire connection would "lock up" in a way. I couldn't connect to anything until I rebooted my computer
View 4 Replies View RelatedDo you now if it is possible to disable the xlate for some connection?
The ASA has some concurrent session limitation that, I think, is related to xlate connections.
As my firewall is not performing any kind of NAT, is it possible to disabe xlate for some connections.
I saw some options like nat exemption, but i not sure if the xlate still being create even if we don't have a NAT translation.
What is the impact of disabling xlate in FWSM
We have dynamic NAT configured from inside to outside interface, but still it is showing NAT entry as below.
"NAT from inside:177.26.99.10 to outside:177.26.99.10 flags Ii"
Expected NAT entry should as below :
"NAT from inside:177.26.99.10 to outside:111.111.111.111 flags Ii"
We were considering implementing "ip verify revert-path" .Hence here i am thinking whether xlate-bypass is the issue here and implementing same with "ip verify revert-path" woud be a good idea.
I have ASA that just started to reboot through out the day yesterday. It seems to happen every few hours but not in a pattern.Right before it reboots there is a flood of sys log id 305006 messages "portmap translation creation failed for tcp src inside:xxx dst outside:xxx the xlats go from around 2-3k to about 30+k then crash.Memory ussage is already pretty high normally on this device (about %75 used) CPU is around %15-20 I notice that the portmap translation errors are always from 3 inside host.
View 4 Replies View Relatedwe have two ASA 5520, on the failover unit is showing LU allocate xlate failed. We read on [URL] that it could be a memory problem , but have cheked it and we have 85% of memory free on both nodes. We also can see all xlate on failover unit.
We have forced failover this evenig and we can´t stablish outbound connexions by outside interface, we think xlates or nat cant work properly.
I got an asa5510. After problems with ipsec connections the log said :
LU allocate xlate failed this error repeats every minute. At the cisco site i found the following :
explantion : stateful failover failed to allocate a translation (xlate) slot record recommended Action : check the available memory by using the show memory command to make sure that the security appliance had free memory in the system. If no memory is available, add more memory
But when i do there is free memory. (about 54%)
What can i do to fix this ?
How to schedule automatic Xlate sessions cleaning in ASA5550. I want to clear few global nat sessions manually every week.Is there any way to automate that?
View 1 Replies View RelatedI have FWSM running version 3.2(23) , configured with interface vlans , all having the same security level , except outside interface vlan which has security level 0 , also same-security-traffic permit inter-interface and same-security-traffic permit intra-interface are configured, my problem is when establishing sessions (I tried TCP only using ssh and telnet , in addition of ping ) from one specific vlan (172.16.1.0/28) to other vlan (172.16.1.16/28) , I can not see the established sessions in "show xlate debug" output ! although I can see these sessions from capture ! the two subnets are separate , two different /28.
I can see the session established from the remaining interface vlans with same security level toward 172.16.1.16/28 , my question is what is the exception with vlan having this subnet172.16.1.0/28, how it can reach other vlan with subnnet 172.16.1.16/28 without showing anything in xlate table ? do you thing it is bug ?
We recently changed ISPs from Verizon T1 to Comcast fiber.
The only change made in the firewall was the outside IP address, gateway and mask. No changes on the internal network or the interface.
After a power cycle everything is good from anywhere from 24-48 hours, then all traffic locks up. The interrface shows as being up but no traffic can get through until another power cycle.
I'm new to an ASA 5510 running 8.4(3) and am trying to figure out something regarding time ranges in ASDM. I simply want to allow a single port during business hours only (I'm not concerned about open sessions needing to be closed). So as an example I add a rule something like:
(RULE1 on the internal interface) SRC=INTERNAL DEST=ANY SERVICE=RDP ACTION=PERMIT with a time range set for weekdays 8:00-16:59. I did a test after 5pm on a weekday and was still allowed to do RDP to a server (from INTERNAL), and after using the packet trace tool saw it was still passing through due to a rule a couple lines down (rule 4) that allowed a port range that happened to include port 3389. So my question is if I specify an "allowed" time range and someone attempts access outside that time range, why doesn't it drop it right there? I guess I'm assuming that anything outside the "allowed" time range would be dropped but that doesn't seem to be the case. I'm also assuming the rule base is processed top to bottom.
We just had an issue with our failover unit reloading. In perusing the logs there were a number of %ASA-3-210007:
LU allocate x late failed, errors prior to the reload. These units had just had their OS upgraded to fix a DOS issue a few weeks ago. I have not seen the error since it reloaded. However, I was asked to report the issue just in case it is a bug in the new version of the OS.Two units in failover.
Cisco Adaptive Security Appliance Software Version 8.0(5)9 Device Manager Version 6.0(2). Compiled on Mon 01-Feb-10 10:36 by buildersSystem image file is
"disk0:/asa805-9-k8.bin"Config file at boot was "startup-config"
CP-ASA up 17 days 21 hoursfailover cluster up 17 days 22 hours
[code]....
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" .
We have a user who needs to access a vpn from his MAC through an ASA 5505. The user is getting an IP via DHCP and the outside interface of the ASA gets it's address via DHCP as well. The user states that when he is home or anywhere else but behind the ASA it connects fine, but once the ASA is added it times out. He is able to get to the internet from the machine without any issues. Looking over the config on the firewall it isn't set to deny any traffic and there is a global set on the interface and it is nat the inside interface. There is no global policy in place so I was considering implementing the following:
policy-map global_policyclass inspection_default inspect pptp
192.168.1.10 --> ASA 1-----> ASA 2-------> ASA 3----> server (172.21.16.15)
We have opened 3389 , 80 & 445 ports on all firewalls ( ASA 1, ASA 2, ASA ) for server (172.21.16.15) from (192.168.1.10).We are able to see connection in ASA 1 under show connection for 3389, 445 ,80.
We are not able to see connections in ASA 2 & ASA 3 under show connection for 3389. But we are able to see hits in ACl.
Is it possible to have a Cisco ASA5510 with two internet connections performing as follows.
Internet A---------All traffic except LAN to LAN vpn
Internet B---------LAN to LAN vpn
I cant find anything definitive on google to say it will or wont, i know it cant do policy based routing.
We are implementing an ASA 5510 firewall with DMZ. Our UDP packets are able to get outside the firewall, but our TCP packets are being denied because of no connection. I've attached the config file and log file.
View 2 Replies View RelatedWe are in the process of getting two new connections pulled in that I would like to utilize in the following configuration.
DS3 - 45/45 I would like to use this circuit for all of our servers to NAT out of as well as our VPN tunnel to our remote site. It will be much more reliable than our cable line.
Cable Internet - 50/10 I would like to use this for all internet traffic that users generate. I would like to be able to fail over to the DS3 if this line goes down.
To get all traffic go out the cable line would take a dynamic NAT rule and a default route. How would I automate a failover to the DS3 with a backup route and dynamic NAT rule?
I understand that if the DS3 goes down it will take manual intervention to bring the tunnel back up and servers with static NAT will need reconfiguration.
We have a second ASA 5510 that is suppose to be a hot standby. I need to find out that, as a hot standby, does it have to have the same licenses as the ASA that it backs up. We purchased 50 SSL VPN licenses for that unit. If it fails over, we need to make sure the failover asa can allow SSL VPN connections.
View 3 Replies View RelatedI am trying to get up to speed on this topic as quickly as possible.
Here is my issue:
1) We are able to access the webiste
2) We are able to upload data packets
3) We allow the website to time out while we are uploading data packets
4) When we attempt to re-access the website the ip is blocked a) this includes pinging and trace
5) After an undertermined period of time the ip is unblocked and we are allowed to access it again.
The ASA 5505 router is the last forward facing stop before entering the VPN tunnel. We have tested by circumventing the ASA and we are unable to duplicate the disconnect. We have reviewed the config file and have not been able to identify what rule/settings could be affecting this.
when tracing port usage, the actions use 2 tcp ports and 1 udp port, the 2 tcp ports open and close by each transaction, when the ip block occures the 2 tcp ports are "dead" the udp port remains open (appearhently sending the remainder of the data packets)
When we say that ASA 5505 supports 10k connections does it mean that we can have 10k connections to the different websites?
View 5 Replies View Relatedi have two CAT3750 need to place in L3, and it supposed that used as L3 switches by SVI for L2 routing, and I want to these two configured as redundancy by HSRP. but now I can only have one ASA5540 to connects these of L3 switches.
so, here is my questions:
1. does ASA5540 support multi vlan?
2. does it support spanning tree protocol?
3. if I've choiced to use trunking between two L3 switches, does it can pass through HSRP hello msg?
4. achive network redundancy
I've got a problem on 887VAMG router. It drops important connections. As customer wants to have a firewall I created ACL and ip inspect rules ,but the router drops their connections to cloud and some websites are not opening. So I removed ACL and most ip inspect rules just to test if it effects that. And left only ip inspect http urlfilter. But still they have those problems, so I'm really stuck how to configure that firewall. The below some dropping connection review:
%FW-6-DROP_PKT: Dropping tcp session due to RST inside current window with ip ident 13968 tcpflags 0x5014 seq.no 1629693318 ack 1687676045
000049: Mar 6 11:49:21.324: %FW-6-DROP_PKT: Dropping http session <ip>:1766 69.171.242.12:80 with ip ident 26247 tcpflags 0x5018 seq.no 264144210 ack 642133125
000050: Mar 6 11:50:00.774: %FW-6-DROP_PKT: Dropping http session <ip>:4708 69.171.242.12:80 with ip ident 2425 tcpflags 0x5018 seq.no 3819869211 ack 1862176018
000051: Mar 6 11:50:52.515: %FW-6-DROP_PKT: Dropping http session <ip>:2599 173.194.34.90:80 due to RST inside current window with ip ident 22909 tcpflags 0x5014 seq.no 899975979 ack 92642430
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I need to block 4000 nodes (Ultrasurf, TOR exit nodes) and I've written a script that will ssh and copy in these objects (prob 100 at a time) into an object group and then put a blanket deny. I don't see a flood of traffic (occassional hits every other day, etc) but I was wondering what the impact would be? Can the ASA handle an object group of that size plus an ACL with it? Any way to block incoming connections from TOR/Ultrasurf?
View 1 Replies View RelatedHow do I monitor connections to the DMZ port on our ASA 5505 (via ASDM 5.2)? We have a WAP connected to it and it's intermittently dropping connections.
View 2 Replies View RelatedHow to configure our ASA to nat our to internetconnections, at the moment the first work fine,
ISP1 NAT
ASA5510 LAN
ISP2 NAT
I have an ASA 5505 with Security Bundle license.
I am able to create 2 LAN networks (192.168.9.0 and 172.16.9.0) Vlan1 and Vlan12 respectively. I also setup 2 outside interfaces (outside1 and outside2).
Network 1 (192.168.9.0 - VLAN1) has no issues going out via Outside1, however I can't get Network 2 (172.16.9.0 - VLAN 12) to go thru outside2.
I put in a static route (route outside 172.16.9.0 255.255.255.0 x.x.x.x), the x.x.x.x is the default gateway of my ISP.
There is a 6500 switch with fwsm. We have extended 2 vlans from the ISP into the FWSM. Also there are atleast 10 other vlans for our internal network. We would like say half of the internal vlans to go out of the 1st ISP vlan and the remaining half from the 2nd ISP vlan. Is there a way we can do this in the FWSM?
View 2 Replies View RelatedWe have a PIX 501 and I'm in the process of replacing it with a ASA5505. We're currently using the 501 for a site-to-site vpn for disaster recovery purposes and I'm trying to verify the number of concurrent connections we can have.
View 1 Replies View RelatedI am having issues trying to track down what is causing a high number of connection on our FWSM in our core 6509 switch. I recently upgraded my FWSM to 3.1(20) and I'm looking for a tool to be able to find the culprit. When I receive these messages I try to get onto the firewall in time to be able to get information regarding this issue but by the time I do the device recovers. Is there a way to tweat the threshold of the SNMP trap for high connections? Is there any way I can retreive this information via SNMP? Is there are command that will allow me to extract the local IP making the most connections?
View 1 Replies View RelatedI am on version 8.2(1) of ASA Code.When accessing a SQL server on a secure internal interface,(Traffic is sourcing from DMZ) i'm getting some timeouts on the initial connection on port 1433. All subsequent connections work fine. Packet tracer shows the connection builds properly, and shouldn't have a connectivity issue. The problem server is a webserver that connects back through the firewall to access the SQL server on port 1433. We also have many other webservers in the DMZ which access the same SQL server, but do not have the same timeout issues. Here are my timeouts, from the config
timeout xlate 3:00:00
timeout conn 1:00:00 half-closed 0:10:00 udp 0:02:00 icmp 0:00:02
timeout sunrpc 0:10:00 h323 0:05:00 h225 1:00:00 mgcp 0:05:00 mgcp-pat 0:05:00
timeout sip 0:30:00 sip_media 0:02:00 sip-invite 0:03:00 sip-disconnect 0:02:00
timeout sip-provisional-media 0:02:00 uauth 0:05:00 absolute
timeout tcp-proxy-reassembly 0:01:00
arp timeout 14400
I've seen a couple articles about increasing the tcp timeout to 3 hours for the DMZ interface?
RV082 - 1.3.2 I need to have RDP and pcAnywhere enabled to a customer site for remote support, but need to limit the incoming IP ranges to only our offices. I have the port forwarding set up and tested working. I then set up rules to deny all traffic on the needed ports and added rules to allow a few IP ranges from our office locations. I even tried a rule allowing all traffic from our main office but that also failed to allow RDP or pcAnywere connections.Now I can no longer connect from any of our remote offices. I followed the limited instructions that I found in another post but its not working.
View 1 Replies View Related