SSH to an internal Router through 5508-X GE02

[fbeye]

Hello

I was both curious for the sake of knowledge but also because I have no available Interfaces to connect my 891f to to SSH into from the Internet.

The GE Interface on my 5508-X is 192.168.1.1 and is enabled for ASDM connectivity.

I connected it to an 891f and from the 891f I can ping the 192.168.1.1 on the 5508, I can ping 192.168.1.2 (891f WAN), 192.168.8.1 (Vlan Interface) and 192.168.8.2 (Laptop connected to FE0 on the 891. The Laptop can also ping to the 891 as well as the GE02 on the 5508.

Long story short is the routes and connectivity seems correct but I am having troubling pinging the Internet. Is the GE2 (ASDM) straight up incapable of seeing the Internet for security reasons or am I just not allowing it correctly .Essentially I want to connect to the 891f Route SSH (192.168.1.2) through my 5508-X WAN.

[fbeye]

Well I seem to have made an error. I rebooted the Router and it indeed saved.

here is the weird thing; when I do show running-config in CLI it shows my existing configuration as far as ACL’s but in ASDM it just shows the 2 new one.. But the ACLS are not active in a sense because I can not access my email server. It’s weird because the CLI shows the ACL but ASDM does not.

[Muhammad Awais Khan]

Hi,

can you share your config so we can validate why exchange is not accessible ?

[fbeye]

I apologize Prior to this message I had compared the current with the original running-config (I had saved in a txt) and asked from the new lines added for new ACL, everything was exactly the same in the same spot. So I deleted the new line plus all the original ACL’s (like 3 or 4 wasn’t a big deal) and typed them back in exactly as they were and they reappeared. Don’t look maybe I have a setting where CLI overrules ASDM but as you said it should add to it, not erase it. But it wasn’t a full erase it just wasn’t appearing in ASDM.
At this point everything is inputted and everything works. I just hope I don’t have a glitchy 5508 where anything I do CLI erases my ASDM configurations

[fbeye]

Hello I apologize for the delay.

So, if I add ;

object-group network INSIDE_NETWORK
subnet 192.168.1.0 255.255.255.0
nat (inside,outside) dynamic interface

Everything on my existing running-config still works but when I add;

object network obj_192.168.1.2
host 192.168.1.2
nat (inside,outside) static interface service tcp ssh 22

access-list OUTSIDE extended permit tcp any host 192.168.1.2 eq 22
access-group OUTSIDE in interface outside

EVERYTHING on my existing running-config I still there as well as these added but now I can not access my email server on the x.x.x.180 IP using smtpd and imapssl

Here is the running-config that is exactly like the one I posted earlier but with the added 5 lines which #1 disables my ability to access my email and #2 shows up as it always did on the config but now #3 in my ASDM it does not show them, only the new 4 lines and yet the |show running-config" does.

: Serial Number: JAD192402FY
: Hardware: ASA5508, 8192 MB RAM, CPU Atom C2000 series 2000 MHz, 1 CPU (8 cores)
:
ASA Version 9.6(2)2
!
hostname ciscoasa
enable password $sha512$5000$VxGVpbbYO1zrechJNeV1wg==$GTQ23G8/TbyeZGPCsWdOjA== pbkdf2
names
ip local pool VPNPool 10.0.3.101-10.0.3.105 mask 255.255.255.0

!
interface GigabitEthernet1/1
description WAN
nameif outside
security-level 0
pppoe client vpdn group pppoewan
ip address pppoe setroute
!
interface GigabitEthernet1/2
nameif inside
security-level 100
ip address 192.168.1.1 255.255.255.0
!
interface GigabitEthernet1/3
description TPLink
nameif tplink
security-level 100
ip address 192.168.2.1 255.255.255.0
!
interface GigabitEthernet1/4
description mail
nameif mail
security-level 100
ip address 192.168.3.1 255.255.255.0
!
interface GigabitEthernet1/5
description fhc
nameif fhc
security-level 100
ip address 192.168.4.1 255.255.255.0
!
interface GigabitEthernet1/6
description vpn
nameif vpn
security-level 100
ip address 192.168.5.1 255.255.255.0
!
interface GigabitEthernet1/7
description Open
nameif Open
security-level 90
ip address 10.0.1.115 255.255.255.0
!
interface GigabitEthernet1/8
description NAS
nameif NAS
security-level 90
ip address 10.0.2.115 255.255.255.0
!
interface Management1/1
management-only
no nameif
no security-level
no ip address
!
ftp mode passive
dns domain-lookup outside
dns domain-lookup inside
dns domain-lookup tplink
dns domain-lookup mail
dns domain-lookup fhc
dns domain-lookup vpn
dns domain-lookup Open
dns domain-lookup NAS
same-security-traffic permit inter-interface
same-security-traffic permit intra-interface
object network TPLink
host 192.168.2.177
description TPLink
object network mail
host 192.168.3.180
description mail
object network fhc
host 192.168.4.181
description fhc
object network dlink
host 192.168.5.178
description dlink
object network Inside
subnet 192.168.1.0 255.255.255.0
object network obj_192.168.1.2
host 192.168.1.2
object-group network DM_INLINE_NETWORK_1
network-object host X.X.X.180
network-object object mail
object-group service imapssl tcp
description imapssl
port-object eq 993
object-group network DM_INLINE_NETWORK_4
network-object host X.X.X.180
network-object object mail
object-group network DM_INLINE_NETWORK_2
network-object host X.X.X.180
network-object object mail
object-group network DM_INLINE_NETWORK_3
network-object host X.X.X.180
network-object object mail
object-group protocol TCPUDP
protocol-object udp
protocol-object tcp
object-group service smtpd tcp
description smtpd
port-object eq 587
object-group network DM_INLINE_NETWORK_5
network-object host X.X.X.180
network-object object mail
object-group network DM_INLINE_NETWORK_6
network-object host X.X.X.180
network-object object mail
object-group network DM_INLINE_NETWORK_7
network-object host X.X.X.180
network-object object mail
object-group protocol DM_INLINE_PROTOCOL_1
protocol-object udp
protocol-object tcp
object-group service email tcp
port-object eq 993
access-list outside_access_in extended permit tcp any object-group DM_INLINE_NETWORK_3 eq ssh
access-list SPLIT_TUNNEL standard permit 10.0.2.0 255.255.255.0
access-list vpn_access_in extended permit ip any any
access-list outside_access_in_1 extended permit tcp any object-group DM_INLINE_NETWORK_5 object-group imapssl
access-list outside_access_in_1 extended permit tcp any object-group DM_INLINE_NETWORK_6 object-group smtpd
access-list outside_access_in_1 extended permit tcp any object-group DM_INLINE_NETWORK_7
access-list OUTSIDE extended permit tcp any host 192.168.1.2 eq ssh
pager lines 24
logging asdm informational
mtu outside 1500
mtu inside 1500
mtu tplink 1500
mtu mail 1500
mtu fhc 1500
mtu vpn 1500
mtu Open 1500
mtu NAS 1500
no failover
no monitor-interface service-module
icmp unreachable rate-limit 1 burst-size 1
no asdm history enable
arp timeout 14400
no arp permit-nonconnected
arp rate-limit 16384
!
object network TPLink
nat (any,any) static X.X.X.177
object network mail
nat (any,any) static X.X.X.180
object network fhc
nat (any,any) static X.X.X.181
object network dlink
nat (any,any) static X.X.X.178
object network obj_192.168.1.2
nat (inside,outside) static interface service tcp ssh ssh
access-group OUTSIDE in interface outside
access-group vpn_access_in in interface vpn
route outside 0.0.0.0 0.0.0.0 X.X.X.182 1
timeout xlate 3:00:00
timeout pat-xlate 0:00:30
timeout conn 1:00:00 half-closed 0:10:00 udp 0:02:00 sctp 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
timeout floating-conn 0:00:00
timeout conn-holddown 0:00:15
user-identity default-domain LOCAL
http server enable
http 192.168.1.0 255.255.255.0 inside
no snmp-server location
no snmp-server contact
service sw-reset-button
crypto ipsec security-association pmtu-aging infinite
crypto ca trustpoint _SmartCallHome_ServerCA
no validation-usage
crl configure
crypto ca trustpool policy
crypto ca certificate chain _SmartCallHome_ServerCA
certificate ca 18dad19e267de8bb4a2158cdcc6b3b4a
308204d3 308203bb a0030201 02021018 dad19e26 7de8bb4a 2158cdcc 6b3b4a30
0d06092a 864886f7 0d010105 05003081 ca310b30 09060355 04061302 55533117
30150603 55040a13 0e566572 69536967 6e2c2049 6e632e31 1f301d06 0355040b
13165665 72695369 676e2054 72757374 204e6574 776f726b 313a3038 06035504
0b133128 63292032 30303620 56657269 5369676e 2c20496e 632e202d 20466f72
20617574 686f7269 7a656420 75736520 6f6e6c79 31453043 06035504 03133c56
65726953 69676e20 436c6173 73203320 5075626c 69632050 72696d61 72792043
65727469 66696361 74696f6e 20417574 686f7269 7479202d 20473530 1e170d30
36313130 38303030 3030305a 170d3336 30373136 32333539 35395a30 81ca310b
30090603 55040613 02555331 17301506 0355040a 130e5665 72695369 676e2c20
496e632e 311f301d 06035504 0b131656 65726953 69676e20 54727573 74204e65
74776f72 6b313a30 38060355 040b1331 28632920 32303036 20566572 69536967
6e2c2049 6e632e20 2d20466f 72206175 74686f72 697a6564 20757365 206f6e6c
79314530 43060355 0403133c 56657269 5369676e 20436c61 73732033 20507562
6c696320 5072696d 61727920 43657274 69666963 6174696f 6e204175 74686f72
69747920 2d204735 30820122 300d0609 2a864886 f70d0101 01050003 82010f00
3082010a 02820101 00af2408 08297a35 9e600caa e74b3b4e dc7cbc3c 451cbb2b
e0fe2902 f95708a3 64851527 f5f1adc8 31895d22 e82aaaa6 42b38ff8 b955b7b1
b74bb3fe 8f7e0757 ecef43db 66621561 cf600da4 d8def8e0 c362083d 5413eb49
ca595485 26e52b8f 1b9febf5 a191c233 49d84363 6a524bd2 8fe87051 4dd18969
7bc770f6 b3dc1274 db7b5d4b 56d396bf 1577a1b0 f4a225f2 af1c9267 18e5f406
04ef90b9 e400e4dd 3ab519ff 02baf43c eee08beb 378becf4 d7acf2f6 f03dafdd
75913319 1d1c40cb 74241921 93d914fe ac2a52c7 8fd50449 e48d6347 883c6983
cbfe47bd 2b7e4fc5 95ae0e9d d4d143c0 6773e314 087ee53f 9f73b833 0acf5d3f
3487968a ee53e825 15020301 0001a381 b23081af 300f0603 551d1301 01ff0405
30030101 ff300e06 03551d0f 0101ff04 04030201 06306d06 082b0601 05050701
0c046130 5fa15da0 5b305930 57305516 09696d61 67652f67 69663021 301f3007
06052b0e 03021a04 148fe5d3 1a86ac8d 8e6bc3cf 806ad448 182c7b19 2e302516
23687474 703a2f2f 6c6f676f 2e766572 69736967 6e2e636f 6d2f7673 6c6f676f
2e676966 301d0603 551d0e04 1604147f d365a7c2 ddecbbf0 3009f343 39fa02af
33313330 0d06092a 864886f7 0d010105 05000382 01010093 244a305f 62cfd81a
982f3dea dc992dbd 77f6a579 2238ecc4 a7a07812 ad620e45 7064c5e7 97662d98
097e5faf d6cc2865 f201aa08 1a47def9 f97c925a 0869200d d93e6d6e 3c0d6ed8
e6069140 18b9f8c1 eddfdb41 aae09620 c9cd6415 3881c994 eea28429 0b136f8e
db0cdd25 02dba48b 1944d241 7a05694a 584f60ca 7e826a0b 02aa2517 39b5db7f
e784652a 958abd86 de5e8116 832d10cc defda882 2a6d281f 0d0bc4e5 e71a2619
e1f4116f 10b595fc e7420532 dbce9d51 5e28b69e 85d35bef a57d4540 728eb70e
6b0e06fb 33354871 b89d278b c4655f0d 86769c44 7af6955c f65d3208 33a454b6
183f685c f2424a85 3854835f d1e82cf2 ac11d6a8 ed636a
quit
telnet timeout 5
ssh stricthostkeycheck
ssh timeout 5
ssh key-exchange group dh-group1-sha1
console timeout 0
vpdn group pppoewan request dialout pppoe
vpdn group pppoewan localname malleomatthew
vpdn group pppoewan ppp authentication chap
vpdn username malleomatthew password *****

dhcpd auto_config outside
!
dhcpd address 192.168.1.5-192.168.1.254 inside
dhcpd enable inside
!
threat-detection basic-threat
threat-detection scanning-threat shun
threat-detection statistics access-list
no threat-detection statistics tcp-intercept
webvpn
enable outside
anyconnect image disk0:/anyconnect-win-4.4.04030-webdeploy-k9.pkg 1
anyconnect enable
tunnel-group-list enable
cache
disable
error-recovery disable
group-policy GroupPolicy_HomeVPN internal
group-policy GroupPolicy_HomeVPN attributes
wins-server none
dns-server value 205.171.3.65
vpn-tunnel-protocol ssl-clientless
split-tunnel-policy tunnelspecified
split-tunnel-network-list value SPLIT_TUNNEL
default-domain none
dynamic-access-policy-record DfltAccessPolicy
username CiscoVPN password J7YMLltuBD0Gdxvn encrypted
tunnel-group HomeVPN type remote-access
tunnel-group HomeVPN general-attributes
address-pool VPNPool
default-group-policy GroupPolicy_HomeVPN
tunnel-group HomeVPN webvpn-attributes
group-alias HomeVPN enable
!
class-map inspection_default
match default-inspection-traffic
!
!
policy-map type inspect dns preset_dns_map
parameters
message-length maximum client auto
message-length maximum 512
no tcp-inspection
policy-map global_policy
class inspection_default
inspect dns preset_dns_map
inspect ftp
inspect h323 h225
inspect h323 ras
inspect rsh
inspect rtsp
inspect sqlnet
inspect skinny
inspect sunrpc
inspect xdmcp
inspect sip
inspect netbios
inspect tftp
inspect ip-options
inspect icmp
!
service-policy global_policy global
prompt hostname context
no call-home reporting anonymous
Cryptochecksum:b27e5de887e4ed01defab9420a19b43a
: end

[Muhammad Awais Khan]

hi,

the reason behind your mail service disruption is that you basically overwrite the existing access-group statement by applying below:

access-group OUTSIDE in interface outside

you need to remove above and add:

access-group outside_access_in_1 in interface outside

Once done, please add the new ACL Entry for SSH to your existing ACL outside_access_in_1 through ASDM or CLI, with CLI it look like below:

access-list outside_access_in_1 extended permit tcp any host 192.168.1.2 eq ssh

[fbeye]

Ok so I understand what is happening but I also want to know why and how you see this through the running-config.

by creating “access-group OUTSIDE in interface outside“ it moved the existing one to “access-group outside_access_in_1 in interface outside” which made it (original) secondary and made the new one for ssh the new one? 

[Muhammad Awais Khan]

actually by creating "“access-group OUTSIDE in interface outside“ it removes the orignal entry. There is no secondary concept here. It can be only one. so whenever you apply acces-group to any interface, it will remove and overwrite any existing access-group entry

So from your running config, i notice two different Access-lists created for outside traffic which gives me hint about the issue while only single Access-list can be applied to interface

[fbeye]

I understand what you mean now. I have it all set up and entries are both in CLI as well as ASDM.

I was curious about one last tidbit. Do I need both of these entries?;

object network INSIDE_NETWORK
subnet 192.168.1.0 255.255.255.0
nat (inside,outside) dynamic interface

and

object network obj_192.168.1.2
host 192.168.1.2
nat (inside,outside) static interface service tcp ssh 2000

I understand the first essentially is a NAT allowing the dynamic subnet of 192.168.1.x internet access out through the "outside" interface but wouldn't the 2nd object network be permitted just by having

access-list outside_access_in_1 extended permit tcp any host 192.168.1.2 eq ssh 2000
access-group outside_access_in_1 in interface outside

or does the 2nd network object redirect the incoming port 2000 to the specific 192.168.1.2 addy and that is why?

[fbeye]

Never mind.

Am I safe to say that I need the second entry for NAT to actually tell incoming ssh connections to go to 192.168.1.2 whereas the access-list is the actual permission and that the first NAT simply allows the subnet of 192.168.1.0 access to the outside (internet).

[Muhammad Awais Khan · Accepted solution]

Hi

You are correct with first statement that below will allow you to have internet access from inside subnet mapped to outside interface address but for incomming ssh traffic, permitting access-list will not be enough as access-list will just allow the traffic to reach Outside interface on port 2000, but to translate this address to internal address, NAT entry is required

--to allow internet from inside to outside with translation to outside interface IP Address

object network INSIDE_NETWORK
subnet 192.168.1.0 255.255.255.0
nat (inside,outside) dynamic interface

--To allow SSH from outside

object network obj_192.168.1.2
host 192.168.1.2
nat (inside,outside) static interface service tcp ssh 2000

and yes you are spot on here in this statement/ "Am I safe to say that I need the second entry for NAT to actually tell incoming ssh connections to go to 192.168.1.2 whereas the access-list is the actual permission and that the first NAT simply allows the subnet of 192.168.1.0 access to the outside (internet).

[fbeye]

Thank you for all of your help and wisdom. I learned a lot and with that I got it all set up the way I had wanted.

Thank you  

[Muhammad Awais Khan]

i am glad that posts here make things worked out for u. keep posting in the comunity for any further query and feel free to ping me for any further info :)

--

rate the posts helpful/accepted as solution if it helped you out