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Old 11-24-2006, 11:37 AM   #1
ehab_8
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Registered: Nov 2006
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Question Blocking all ports

Dear,

How can I block all the ports except SSH port (22.

please advice...
 
Old 11-24-2006, 11:41 AM   #2
amitsharma_26
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iptables -A INPUT/FORWARD -p tcp --dport ! 22 -j DROP
 
Old 11-25-2006, 04:18 PM   #3
ehab_8
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hi
thank you very much...
Last edited by ehab_8; 11-25-2006 at 05:05 PM.
 
Old 11-25-2006, 10:43 PM   #4
ehab_8
LQ Newbie
 
Registered: Nov 2006
Posts: 5

Original Poster
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Hi,
thank you amitsharma_26 again for your help,
It's work fine all tcp ports except SSH port (22) block but other ports still open, so please how can I block all other ports please ?

Code:
[root@localhost ~]# netstat -n
Active Internet connections (w/o servers)
Proto Recv-Q Send-Q Local Address               Foreign Address             State
Active UNIX domain sockets (w/o servers)
Proto RefCnt Flags       Type       State         I-Node Path
unix  17     [ ]         DGRAM                    8063   /dev/log
unix  2      [ ]         DGRAM                    9197   @/var/run/hal/hotplug_socket
unix  2      [ ]         DGRAM                    5165   @udevd
unix  3      [ ]         STREAM     CONNECTED     20102  /tmp/.X11-unix/X0
unix  3      [ ]         STREAM     CONNECTED     20101
unix  2      [ ]         DGRAM                    20087
unix  3      [ ]         STREAM     CONNECTED     20076  /tmp/.X11-unix/X0
unix  3      [ ]         STREAM     CONNECTED     20075
unix  3      [ ]         STREAM     CONNECTED     16432  /tmp/.X11-unix/X0
unix  3      [ ]         STREAM     CONNECTED     16431
unix  2      [ ]         DGRAM                    16412
unix  3      [ ]         STREAM     CONNECTED     16400  /tmp/.X11-unix/X0
unix  3      [ ]         STREAM     CONNECTED     16399
unix  2      [ ]         DGRAM                    14964
unix  3      [ ]         STREAM     CONNECTED     14712  /tmp/orbit-root/linc-c7c-0-592155985c1f9unix  3      [ ]         STREAM     CONNECTED     14711
unix  3      [ ]         STREAM     CONNECTED     14708  /tmp/orbit-root/linc-bed-0-2cec8f59cceedunix  3      [ ]         STREAM     CONNECTED     14707
unix  3      [ ]         STREAM     CONNECTED     14689  /tmp/.X11-unix/X0
unix  3      [ ]         STREAM     CONNECTED     14688
unix  3      [ ]         STREAM     CONNECTED     13748
unix  3      [ ]         STREAM     CONNECTED     13747
unix  3      [ ]         STREAM     CONNECTED     13731  /tmp/orbit-root/linc-c41-0-4ceabaf76953cunix  3      [ ]         STREAM     CONNECTED     13730
unix  3      [ ]         STREAM     CONNECTED     13729  /tmp/orbit-root/linc-bf2-0-7b74882139fffunix  3      [ ]         STREAM     CONNECTED     13728
unix  3      [ ]         STREAM     CONNECTED     13727  /tmp/orbit-root/linc-c41-0-4ceabaf76953cunix  3      [ ]         STREAM     CONNECTED     13726
unix  3      [ ]         STREAM     CONNECTED     13723  /tmp/orbit-root/linc-bed-0-2cec8f59cceedunix  3      [ ]         STREAM     CONNECTED     13722
unix  3      [ ]         STREAM     CONNECTED     13719  /tmp/.ICE-unix/2987
unix  3      [ ]         STREAM     CONNECTED     13718
unix  3      [ ]         STREAM     CONNECTED     13713  /tmp/.X11-unix/X0
unix  3      [ ]         STREAM     CONNECTED     13712
unix  3      [ ]         STREAM     CONNECTED     11979  /tmp/orbit-root/linc-c26-0-382f1fe92d280unix  3      [ ]         STREAM     CONNECTED     11978
unix  3      [ ]         STREAM     CONNECTED     11975  /tmp/orbit-root/linc-bed-0-2cec8f59cceedunix  3      [ ]         STREAM     CONNECTED     11974
unix  3      [ ]         STREAM     CONNECTED     11966  /tmp/.ICE-unix/2987
unix  3      [ ]         STREAM     CONNECTED     11965
unix  3      [ ]         STREAM     CONNECTED     11959  /tmp/orbit-root/linc-c10-0-56f916a05db39unix  3      [ ]         STREAM     CONNECTED     11958
unix  3      [ ]         STREAM     CONNECTED     11957  /tmp/orbit-root/linc-c3d-0-24b3a809cf910unix  3      [ ]         STREAM     CONNECTED     11956
unix  3      [ ]         STREAM     CONNECTED     11951  /tmp/orbit-root/linc-c3d-0-24b3a809cf910unix  3      [ ]         STREAM     CONNECTED     11950
unix  3      [ ]         STREAM     CONNECTED     11949  /tmp/orbit-root/linc-bf2-0-7b74882139fffunix  3      [ ]         STREAM     CONNECTED     11948
unix  3      [ ]         STREAM     CONNECTED     11947  /tmp/orbit-root/linc-c3d-0-24b3a809cf910unix  3      [ ]         STREAM     CONNECTED     11946
unix  3      [ ]         STREAM     CONNECTED     11943  /tmp/orbit-root/linc-bed-0-2cec8f59cceedunix  3      [ ]         STREAM     CONNECTED     11942
unix  3      [ ]         STREAM     CONNECTED     11937  /tmp/.X11-unix/X0
unix  3      [ ]         STREAM     CONNECTED     11936
unix  3      [ ]         STREAM     CONNECTED     11921  /tmp/orbit-root/linc-c10-0-56f916a05db39unix  3      [ ]         STREAM     CONNECTED     11920
unix  3      [ ]         STREAM     CONNECTED     11919  /tmp/orbit-root/linc-c3b-0-4333843e8d720unix  3      [ ]         STREAM     CONNECTED     11918
unix  3      [ ]         STREAM     CONNECTED     11913  /tmp/orbit-root/linc-c3b-0-4333843e8d720unix  3      [ ]         STREAM     CONNECTED     11912
unix  3      [ ]         STREAM     CONNECTED     11911  /tmp/orbit-root/linc-bf2-0-7b74882139fffunix  3      [ ]         STREAM     CONNECTED     11910
unix  3      [ ]         STREAM     CONNECTED     11909  /tmp/orbit-root/linc-c3b-0-4333843e8d720unix  3      [ ]         STREAM     CONNECTED     11908
unix  3      [ ]         STREAM     CONNECTED     11905  /tmp/orbit-root/linc-bed-0-2cec8f59cceedunix  3      [ ]         STREAM     CONNECTED     11900
unix  3      [ ]         STREAM     CONNECTED     11895  /tmp/.X11-unix/X0
unix  3      [ ]         STREAM     CONNECTED     11894
unix  3      [ ]         STREAM     CONNECTED     11878  /tmp/orbit-root/linc-c10-0-56f916a05db39unix  3      [ ]         STREAM     CONNECTED     11877
unix  3      [ ]         STREAM     CONNECTED     11876  /tmp/orbit-root/linc-c39-0-4bbd7950bfa8aunix  3      [ ]         STREAM     CONNECTED     11875
unix  3      [ ]         STREAM     CONNECTED     11870  /tmp/orbit-root/linc-c39-0-4bbd7950bfa8aunix  3      [ ]         STREAM     CONNECTED     11869
unix  3      [ ]         STREAM     CONNECTED     11868  /tmp/orbit-root/linc-bf2-0-7b74882139fffunix  3      [ ]         STREAM     CONNECTED     11867
unix  3      [ ]         STREAM     CONNECTED     11866  /tmp/orbit-root/linc-c39-0-4bbd7950bfa8aunix  3      [ ]         STREAM     CONNECTED     11865
unix  3      [ ]         STREAM     CONNECTED     11862  /tmp/orbit-root/linc-bed-0-2cec8f59cceedunix  3      [ ]         STREAM     CONNECTED     11861
unix  3      [ ]         STREAM     CONNECTED     11852  /tmp/.X11-unix/X0
unix  3      [ ]         STREAM     CONNECTED     11851
unix  3      [ ]         STREAM     CONNECTED     11826  /tmp/orbit-root/linc-c10-0-56f916a05db39unix  3      [ ]         STREAM     CONNECTED     11825
unix  3      [ ]         STREAM     CONNECTED     11824  /tmp/orbit-root/linc-c37-0-3eef2a4fb117eunix  3      [ ]         STREAM     CONNECTED     11823
unix  3      [ ]         STREAM     CONNECTED     11818  /tmp/orbit-root/linc-c37-0-3eef2a4fb117eunix  3      [ ]         STREAM     CONNECTED     11817
unix  3      [ ]         STREAM     CONNECTED     11816  /tmp/orbit-root/linc-bf2-0-7b74882139fffunix  3      [ ]         STREAM     CONNECTED     11815
unix  3      [ ]         STREAM     CONNECTED     11814  /tmp/orbit-root/linc-c37-0-3eef2a4fb117eunix  3      [ ]         STREAM     CONNECTED     11813
unix  3      [ ]         STREAM     CONNECTED     11810  /tmp/orbit-root/linc-bed-0-2cec8f59cceedunix  3      [ ]         STREAM     CONNECTED     11809
unix  3      [ ]         STREAM     CONNECTED     11804  /tmp/.X11-unix/X0
unix  3      [ ]         STREAM     CONNECTED     11803
unix  3      [ ]         STREAM     CONNECTED     11795  /tmp/.X11-unix/X0
unix  3      [ ]         STREAM     CONNECTED     11794
unix  3      [ ]         STREAM     CONNECTED     11667  /tmp/mapping-root
unix  3      [ ]         STREAM     CONNECTED     11661  @/tmp/fam-root-
unix  3      [ ]         STREAM     CONNECTED     11660
unix  3      [ ]         STREAM     CONNECTED     11656
unix  3      [ ]         STREAM     CONNECTED     11635  /tmp/orbit-root/linc-c21-0-502db417c9a73unix  3      [ ]         STREAM     CONNECTED     11634
unix  3      [ ]         STREAM     CONNECTED     11633  /tmp/orbit-root/linc-bed-0-2cec8f59cceedunix  3      [ ]         STREAM     CONNECTED     11632
unix  3      [ ]         STREAM     CONNECTED     11631  @/tmp/fam-root-
unix  3      [ ]         STREAM     CONNECTED     11630
unix  3      [ ]         STREAM     CONNECTED     11623  /var/run/dbus/system_bus_socket
unix  3      [ ]         STREAM     CONNECTED     11622
unix  3      [ ]         STREAM     CONNECTED     11621  /tmp/orbit-root/linc-c13-0-4d7ac303613c
unix  3      [ ]         STREAM     CONNECTED     11620
unix  3      [ ]         STREAM     CONNECTED     11612  /tmp/.ICE-unix/2987
unix  3      [ ]         STREAM     CONNECTED     11611
unix  3      [ ]         STREAM     CONNECTED     11610  /tmp/orbit-root/linc-c21-0-502db417c9a73unix  3      [ ]         STREAM     CONNECTED     11605
unix  3      [ ]         STREAM     CONNECTED     11602  /tmp/orbit-root/linc-c21-0-502db417c9a73unix  3      [ ]         STREAM     CONNECTED     11601
unix  3      [ ]         STREAM     CONNECTED     11598  /tmp/orbit-root/linc-bf2-0-7b74882139fffunix  3      [ ]         STREAM     CONNECTED     11597
unix  3      [ ]         STREAM     CONNECTED     11595  /tmp/.X11-unix/X0
unix  3      [ ]         STREAM     CONNECTED     11594
unix  3      [ ]         STREAM     CONNECTED     11570  /var/run/dbus/system_bus_socket
unix  3      [ ]         STREAM     CONNECTED     11569
unix  3      [ ]         STREAM     CONNECTED     11565  /var/run/dbus/system_bus_socket
unix  3      [ ]         STREAM     CONNECTED     11564
unix  3      [ ]         STREAM     CONNECTED     11554  /tmp/orbit-root/linc-c13-0-4d7ac303613c
unix  3      [ ]         STREAM     CONNECTED     11553
unix  3      [ ]         STREAM     CONNECTED     11552  /tmp/orbit-root/linc-bf2-0-7b74882139fffunix  3      [ ]         STREAM     CONNECTED     11551
unix  3      [ ]         STREAM     CONNECTED     11548  @/tmp/fam-root-
unix  3      [ ]         STREAM     CONNECTED     11547
unix  3      [ ]         STREAM     CONNECTED     11538  @/tmp/dbus-Hk6SkHvDIB
unix  3      [ ]         STREAM     CONNECTED     11537
unix  3      [ ]         STREAM     CONNECTED     11534  /tmp/orbit-root/linc-c13-0-4d7ac303613c
unix  3      [ ]         STREAM     CONNECTED     11533
unix  3      [ ]         STREAM     CONNECTED     11529  /tmp/orbit-root/linc-c1a-0-2a38344d2214cunix  3      [ ]         STREAM     CONNECTED     11528
unix  3      [ ]         STREAM     CONNECTED     11527  /tmp/orbit-root/linc-bed-0-2cec8f59cceedunix  3      [ ]         STREAM     CONNECTED     11524
unix  3      [ ]         STREAM     CONNECTED     11523  /tmp/orbit-root/linc-bed-0-2cec8f59cceedunix  3      [ ]         STREAM     CONNECTED     11522
unix  3      [ ]         STREAM     CONNECTED     11515  /tmp/.ICE-unix/2987
unix  3      [ ]         STREAM     CONNECTED     11514
unix  3      [ ]         STREAM     CONNECTED     11509  /tmp/.X11-unix/X0
unix  3      [ ]         STREAM     CONNECTED     11508
unix  3      [ ]         STREAM     CONNECTED     11501  /tmp/orbit-root/linc-c16-0-4d7ac32b4a4d
unix  3      [ ]         STREAM     CONNECTED     11500
unix  3      [ ]         STREAM     CONNECTED     11495  /tmp/orbit-root/linc-bed-0-2cec8f59cceedunix  3      [ ]         STREAM     CONNECTED     11494
unix  3      [ ]         STREAM     CONNECTED     11491  /tmp/.ICE-unix/2987
unix  3      [ ]         STREAM     CONNECTED     11490
unix  3      [ ]         STREAM     CONNECTED     11488  /tmp/orbit-root/linc-c10-0-56f916a05db39unix  3      [ ]         STREAM     CONNECTED     11487
unix  3      [ ]         STREAM     CONNECTED     11486  /tmp/orbit-root/linc-bf2-0-7b74882139fffunix  3      [ ]         STREAM     CONNECTED     11485
unix  3      [ ]         STREAM     CONNECTED     11481  /tmp/orbit-root/linc-c10-0-56f916a05db39unix  3      [ ]         STREAM     CONNECTED     11480
unix  3      [ ]         STREAM     CONNECTED     11477  /tmp/orbit-root/linc-bed-0-2cec8f59cceedunix  3      [ ]         STREAM     CONNECTED     11476
unix  3      [ ]         STREAM     CONNECTED     11473  /tmp/.ICE-unix/2987
unix  3      [ ]         STREAM     CONNECTED     11472
unix  3      [ ]         STREAM     CONNECTED     11467  /tmp/.X11-unix/X0
unix  3      [ ]         STREAM     CONNECTED     11466
unix  3      [ ]         STREAM     CONNECTED     11459  /tmp/.ICE-unix/2987
unix  3      [ ]         STREAM     CONNECTED     11458
unix  3      [ ]         STREAM     CONNECTED     11453  /tmp/.X11-unix/X0
unix  3      [ ]         STREAM     CONNECTED     11452
unix  3      [ ]         STREAM     CONNECTED     11444  /tmp/.X11-unix/X0
unix  3      [ ]         STREAM     CONNECTED     11437
unix  3      [ ]         STREAM     CONNECTED     11566  /tmp/orbit-root/linc-bf6-0-cff6647dc7aa
unix  3      [ ]         STREAM     CONNECTED     11415
unix  3      [ ]         STREAM     CONNECTED     11404  /tmp/orbit-root/linc-bf6-0-cff6647dc7aa
unix  3      [ ]         STREAM     CONNECTED     11403
unix  3      [ ]         STREAM     CONNECTED     11402  /tmp/orbit-root/linc-bf2-0-7b74882139fffunix  3      [ ]         STREAM     CONNECTED     11401
unix  3      [ ]         STREAM     CONNECTED     11356  @/tmp/fam-root-
unix  3      [ ]         STREAM     CONNECTED     11355
unix  3      [ ]         STREAM     CONNECTED     11414  /tmp/.ICE-unix/2987
unix  3      [ ]         STREAM     CONNECTED     11342
unix  3      [ ]         STREAM     CONNECTED     11341  /tmp/.X11-unix/X0
unix  3      [ ]         STREAM     CONNECTED     11340
unix  3      [ ]         STREAM     CONNECTED     11335  /tmp/orbit-root/linc-bf4-0-20da14e173c7aunix  3      [ ]         STREAM     CONNECTED     11334
unix  3      [ ]         STREAM     CONNECTED     11328  /tmp/orbit-root/linc-bed-0-2cec8f59cceedunix  3      [ ]         STREAM     CONNECTED     11327
unix  3      [ ]         STREAM     CONNECTED     11319  /tmp/orbit-root/linc-bf6-0-cff6647dc7aa
unix  3      [ ]         STREAM     CONNECTED     11318
unix  3      [ ]         STREAM     CONNECTED     11315  /tmp/orbit-root/linc-bed-0-2cec8f59cceedunix  3      [ ]         STREAM     CONNECTED     11314
unix  3      [ ]         STREAM     CONNECTED     11274  /tmp/.X11-unix/X0
unix  3      [ ]         STREAM     CONNECTED     11273
unix  3      [ ]         STREAM     CONNECTED     11243  /tmp/orbit-root/linc-bab-0-24113de9f2be4unix  3      [ ]         STREAM     CONNECTED     11242
unix  3      [ ]         STREAM     CONNECTED     11241  /tmp/orbit-root/linc-bf2-0-7b74882139fffunix  3      [ ]         STREAM     CONNECTED     11240
unix  3      [ ]         STREAM     CONNECTED     11184  /tmp/orbit-root/linc-bab-0-24113de9f2be4unix  3      [ ]         STREAM     CONNECTED     11183
unix  3      [ ]         STREAM     CONNECTED     11182  /tmp/orbit-root/linc-bed-0-2cec8f59cceedunix  3      [ ]         STREAM     CONNECTED     11047
unix  2      [ ]         DGRAM                    11030
unix  3      [ ]         STREAM     CONNECTED     11024  /tmp/.X11-unix/X0
unix  3      [ ]         STREAM     CONNECTED     11023
unix  3      [ ]         STREAM     CONNECTED     11015  /tmp/.X11-unix/X0
unix  3      [ ]         STREAM     CONNECTED     11014
unix  3      [ ]         STREAM     CONNECTED     11013
unix  3      [ ]         STREAM     CONNECTED     11012
unix  3      [ ]         STREAM     CONNECTED     10805  /tmp/.font-unix/fs7100
unix  3      [ ]         STREAM     CONNECTED     10804
unix  4      [ ]         STREAM     CONNECTED     10809  /tmp/.X11-unix/X0
unix  3      [ ]         STREAM     CONNECTED     10549
unix  2      [ ]         DGRAM                    10486
unix  3      [ ]         STREAM     CONNECTED     9195   /var/run/dbus/system_bus_socket
unix  3      [ ]         STREAM     CONNECTED     9194
unix  3      [ ]         STREAM     CONNECTED     9165   /var/run/dbus/system_bus_socket
unix  3      [ ]         STREAM     CONNECTED     9164
unix  3      [ ]         STREAM     CONNECTED     9053
unix  3      [ ]         STREAM     CONNECTED     9052
unix  2      [ ]         DGRAM                    8993
unix  2      [ ]         DGRAM                    8960
unix  2      [ ]         DGRAM                    8869
unix  2      [ ]         DGRAM                    8841
unix  2      [ ]         DGRAM                    8821
unix  2      [ ]         DGRAM                    8790
unix  2      [ ]         DGRAM                    8726
unix  2      [ ]         DGRAM                    8623
unix  3      [ ]         STREAM     CONNECTED     8264
unix  3      [ ]         STREAM     CONNECTED     8263
unix  2      [ ]         DGRAM                    8134
unix  2      [ ]         DGRAM                    8083
[root@localhost ~]#
 
Old 11-26-2006, 06:38 AM   #5
amitsharma_26
Member
 
Registered: Sep 2005
Location: New delhi
Distribution: RHEL 3.0/4.0
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For present state of network & connections(on your localbox)..
Code:
netstat -plant  //for tcp
netstat -planu  //for udp
For checking open ports(for local as well any other box connected)
Code:
nmap -P0 -sT -v host-ip/name

Note : Firewall is a way to block ports/connections & shutting down the services is a way of close them.
 
Old 11-26-2006, 04:30 PM   #6
ehab_8
LQ Newbie
 
Registered: Nov 2006
Posts: 5

Original Poster
Rep: Reputation: 0
thank you very much...
its work fine...
 
  


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