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Showing posts from September, 2019

active directory - Installing ADAM on Windows Server 2012

itemprop="text"> I'm currently tasked with moving a Web Application that uses Active Directory Application Management (ADAM) from a 2003 server to a 2012 Server. My question more about any references to install ADAM on Windows 2012. The reference I am going off of is for Windows Server 2003 ( href="http://technet.microsoft.com/en-us/library/cc739247(v=WS.10).aspx" rel="nofollow noreferrer">http://technet.microsoft.com/en-us/library/cc739247(v=WS.10).aspx ) I'm wondering if anyone could guide me to some documentation on how to install ADAM on 2012? UPDATE: I found an application called Active Directory Lightweight Directory Services Setup Wizard. By running that will I get an ADAM instance? Answer As you (correctly) guessed, AD LDS is the new name of the software previously known as ADAM;

active directory - Installing ADAM on Windows Server 2012

I'm currently tasked with moving a Web Application that uses Active Directory Application Management (ADAM) from a 2003 server to a 2012 Server. My question more about any references to install ADAM on Windows 2012. The reference I am going off of is for Windows Server 2003 ( http://technet.microsoft.com/en-us/library/cc739247(v=WS.10).aspx ) I'm wondering if anyone could guide me to some documentation on how to install ADAM on 2012? UPDATE: I found an application called Active Directory Lightweight Directory Services Setup Wizard. By running that will I get an ADAM instance? Answer As you (correctly) guessed, AD LDS is the new name of the software previously known as ADAM; it's no longer a separate product: now it's built-in in the Windows Server OS, and you only need to enable it as you would do with any other server role. Here's the relavant documentation: http://technet.microsoft.com/en-us/library/hh831593.aspx . Caveat: there is no guarantee t

nginx - Redirect HTTP to HTTPS with ldirectord/LVS

itemprop="text"> We're using LVS for load balancing and want to do a 301 redirect for http://example.com to rel="nofollow noreferrer">https://example.com LVS is enabling https without issue, but the http real servers are not being added to the pool (weight of 0). Does LVS not follow 301 redirects? If not, how do I configure ldirectord to send all HTTP traffic to HTTPS? Here is the nginx config: server { listen 80; server_name example.com; return 301 https://example.com$request_uri; } server { listen 443; ssl on; ssl_certificate server.crt; ssl_certificate_key server.key; server_name example.com; # more here } And ldirectord.cf looks like this: virtual=VIP:80 fallback=127.0.0.1:80 real=10.0.0.7:80 masq 5 real=10.0.0.8:80 ma

nginx - Redirect HTTP to HTTPS with ldirectord/LVS

We're using LVS for load balancing and want to do a 301 redirect for http://example.com to https://example.com LVS is enabling https without issue, but the http real servers are not being added to the pool (weight of 0). Does LVS not follow 301 redirects? If not, how do I configure ldirectord to send all HTTP traffic to HTTPS? Here is the nginx config: server { listen 80; server_name example.com; return 301 https://example.com$request_uri; } server { listen 443; ssl on; ssl_certificate server.crt; ssl_certificate_key server.key; server_name example.com; # more here } And ldirectord.cf looks like this: virtual=VIP:80 fallback=127.0.0.1:80 real=10.0.0.7:80 masq 5 real=10.0.0.8:80 masq 5 service=http request="lvs.htm" receive="lvs" virtualhost=example.com scheduler=wlc protocol=tcp checktype=negotiate virtual=V

domain name system - DNS resolve to CNAME which is not my website. Can someone explain?

I have a website at www.grokit.ca hosted on google app engine. If I issue the following command: nslookup -query=any -debug www.grokit.ca ... I get the following output: $ nslookup -query=any -debug www.grokit.ca Server: X.Y.Z.12 Address: X.Y.Z.12#53 ------------ QUESTIONS: www.grokit.ca, type = ANY, class = IN ANSWERS: -> www.grokit.ca canonical name = ghs.googlehosted.com. ttl = 400 AUTHORITY RECORDS: ADDITIONAL RECORDS: ------------ Non-authoritative answer: www.grokit.ca canonical name = ghs.googlehosted.com. Same with dig: dig www.grokit.ca : ; <<>> DiG 9.9.6 <<>> www.grokit.ca ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 34283 ;; flags: qr rd ra; QUERY: 1, ANSWER: 2, AUTHORITY:

domain name system - DNS resolve to CNAME which is not my website. Can someone explain?

I have a website at www.grokit.ca hosted on google app engine. If I issue the following command: nslookup -query=any -debug www.grokit.ca ... I get the following output: $ nslookup -query=any -debug www.grokit.ca Server: X.Y.Z.12 Address: X.Y.Z.12#53 ------------ QUESTIONS: www.grokit.ca, type = ANY, class = IN ANSWERS: -> www.grokit.ca canonical name = ghs.googlehosted.com. ttl = 400 AUTHORITY RECORDS: ADDITIONAL RECORDS: ------------ Non-authoritative answer: www.grokit.ca canonical name = ghs.googlehosted.com. Same with dig: dig www.grokit.ca : ; <<>> DiG 9.9.6 <<>> www.grokit.ca ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 34283 ;; flags: qr rd ra; QUERY: 1, ANSWER: 2, AUTHORITY: 0, ADDITIONAL: 1 ;; OPT PSEUDOSECTION: ; EDNS: version: 0, flags:; udp: 4000 ;; QUESTION SECTION: ;www.grokit.ca. IN A ;; ANSWER SECTION: w

Unix memory management

itemprop="text"> When using top/free to see memory usage in Unix, there're 'used/free/shared/buffers/cached' categories. What do those exactly mean? I've tried to look for a wiki but didn't find detail information. Please advise, thanks. itemprop="text"> class="normal">Answer Most of that information is in the man page for top. Shared: The amount of shared memory used by a task. It simply reflects memory that could be potentially shared with other processes. Free : Actually unused memory. Used : Allocated to processes. Buffers : Memory used for various OS buffers. Such as OS file-structures. Cache : Memory used for various OS caches, generally the block and file caches.

Unix memory management

When using top/free to see memory usage in Unix, there're 'used/free/shared/buffers/cached' categories. What do those exactly mean? I've tried to look for a wiki but didn't find detail information. Please advise, thanks. Answer Most of that information is in the man page for top. Shared: The amount of shared memory used by a task. It simply reflects memory that could be potentially shared with other processes. Free : Actually unused memory. Used : Allocated to processes. Buffers : Memory used for various OS buffers. Such as OS file-structures. Cache : Memory used for various OS caches, generally the block and file caches.

apache 2.2 - File access with hostname or ip only - no domain?

itemprop="text"> Edit: I think part of the problem is I needed to use port 8080, but I'm still getting the "unable to connect" message. Is there anything I need to configure in /etc to make that accessible? -- It seems likely that this is an obvious question, but I'm having trouble tracking down any useful information. Normally when accessing files in a particular directory on a server, I'm able to create a virtual host, assign a domain, root directory location, etc -- however am in a situation where I have server space and need to access files with only a hostname. Is this possible? For example, let's say the hostname is 123hostname.com, and the file I want access to is in /home/sub-directory/filename.php. How do I get at it via a browser? I've tried: href="http://123host

apache 2.2 - File access with hostname or ip only - no domain?

Edit: I think part of the problem is I needed to use port 8080, but I'm still getting the "unable to connect" message. Is there anything I need to configure in /etc to make that accessible? -- It seems likely that this is an obvious question, but I'm having trouble tracking down any useful information. Normally when accessing files in a particular directory on a server, I'm able to create a virtual host, assign a domain, root directory location, etc -- however am in a situation where I have server space and need to access files with only a hostname. Is this possible? For example, let's say the hostname is 123hostname.com, and the file I want access to is in /home/sub-directory/filename.php. How do I get at it via a browser? I've tried: http://123hostname.com/home/sub-directory/filename.php ...and some other variations on that theme (that I can't post because new users are restricted to one link in messages). But generally stuck. Any help -- even i

proxy - Redirect SSH Users for Docker: Gitlab and Docker: Bitbucket

As you already read in the title I am currently running multiple docker containers which are used as git servers and normally should run under port 22. This is obviously not working, but my requests would be the following. Have the following available on port 22: git@HOST - redirected to gitlab docker container bitbucket@HOST - redirected to bitbucket container root@HOST - ( I am not working as root at all, but for understanding reasons ) normal SSH Access to the Docker Mainhost. I know that I would have to sync ssh keys across containers and accounts, but this would not be a big issue, but I have no Idea if it would be possible to build an redirect system. One approach of mine would be to use ForceCommand but I would not be able to Redirect the SSH Key used... Another idea would be to have a small tool on port 22 runni

proxy - Redirect SSH Users for Docker: Gitlab and Docker: Bitbucket

As you already read in the title I am currently running multiple docker containers which are used as git servers and normally should run under port 22. This is obviously not working, but my requests would be the following. Have the following available on port 22: git@HOST - redirected to gitlab docker container bitbucket@HOST - redirected to bitbucket container root@HOST - ( I am not working as root at all, but for understanding reasons ) normal SSH Access to the Docker Mainhost. I know that I would have to sync ssh keys across containers and accounts, but this would not be a big issue, but I have no Idea if it would be possible to build an redirect system. One approach of mine would be to use ForceCommand but I would not be able to Redirect the SSH Key used... Another idea would be to have a small tool on port 22 running which just routes the complete requests between all SSH daemons, but I have not (yet?) found such a tool and do not know if it would be possible to build such a tool

mod rewrite - How does Apache process a path with a percent-encoded URL in it?

itemprop="text"> I ran into an unexpected case of Apache giving me a 404 error instead of letting mod_rewrite handle the path, when one of the percent-encoded path parts was itself a HTTP URL. e.g. "GET /myfolder/http%3A%2F%2Flocalhost%2Fnotify HTTP/1.0" I have an extremely simple rule in the /myfolder/.htaccess file which sends everything that's not a file in /myfolder/ to a script. It works fine with other percent-encoded values, but in this case Apache never processes the RewriteRule from the .htaccess file. I can double-encode the value as a workaround, but it seems that Apache should still process the mod_rewrite phases. I intend the URL merely to be an input parameter to the script. Here are the (ir)relevant mod_rewrite directives in /myfolder/.htaccess: RewriteCond %{REQUEST

mod rewrite - How does Apache process a path with a percent-encoded URL in it?

I ran into an unexpected case of Apache giving me a 404 error instead of letting mod_rewrite handle the path, when one of the percent-encoded path parts was itself a HTTP URL. e.g. "GET /myfolder/http%3A%2F%2Flocalhost%2Fnotify HTTP/1.0" I have an extremely simple rule in the /myfolder/.htaccess file which sends everything that's not a file in /myfolder/ to a script. It works fine with other percent-encoded values, but in this case Apache never processes the RewriteRule from the .htaccess file. I can double-encode the value as a workaround, but it seems that Apache should still process the mod_rewrite phases. I intend the URL merely to be an input parameter to the script. Here are the (ir)relevant mod_rewrite directives in /myfolder/.htaccess: RewriteCond %{REQUEST_FILENAME} !-s RewriteRule .* ./script-the-world.php The rewrite rules are NOT being processed. In the server configuration I've got RewriteLogLevel 5, etc., and tail -f /var/log/http/rewrite.log shows

security - S/MIME certificate to minimize email bounce

itemprop="text"> I have a website hosted in a vps that sends informative emails to my clientes, maybe 20-40 emails per day. Since few weeks ago some sent emails are bouncing with the following error: This message was created automatically by mail delivery software. A message that you sent could not be delivered to one or more of its recipients. This is a permanent error. The following address(es) failed: destination@example.com SMTP error from remote mail server after RCPT TO:: host mx1.emailsrvr.com [173.203.2.36]: 554 5.7.1 ACL dns_rbl; Client host [MY-IP] blocked using sa-dnset.blagr.emailsrvr.com=127.24.0.2 Please visit href="http://bounce.emailsrvr.com/?a0" rel="nofollow noreferrer">http://bounce.emailsrvr.com/?a0 for more information on why this message coul

security - S/MIME certificate to minimize email bounce

I have a website hosted in a vps that sends informative emails to my clientes, maybe 20-40 emails per day. Since few weeks ago some sent emails are bouncing with the following error: This message was created automatically by mail delivery software. A message that you sent could not be delivered to one or more of its recipients. This is a permanent error. The following address(es) failed: destination@example.com SMTP error from remote mail server after RCPT TO:: host mx1.emailsrvr.com [173.203.2.36]: 554 5.7.1 ACL dns_rbl; Client host [MY-IP] blocked using sa-dnset.blagr.emailsrvr.com=127.24.0.2 Please visit http://bounce.emailsrvr.com/?a0 for more information on why this message could not be delivered ------ This is a copy of the message, including all the headers. ------ **MY-IP is the ip of my vps server* Tracking the error according to details in the email body, I found that my ip is blacklisted in Blocklist Removal Center with the following war

domain name system - bind and dns master and slave

itemprop="text"> After going through OReilly dns and bind book, I still have problems with a master and slave configuration, I am getting client 192.168.1.67#34245: update ' .co.uk/IN' denied as a syslog error for the master definintion of the zone. and named[19034]: client 192.168.1.67#47452: update forwarding ' .co.uk/IN' denied as a syslog error for the slave definition The server that has the master zones has a named.conf : options { allow-transfer { 192.168.1/24; }; } // The reverse lookup of 192.168.1.* - the local IP addresses zone "1.168.192.in-addr.arpa" in { type master; file "192.168.1.db"; allow-transfer { key TRANSFER; }; allow-update { key TRANSER; }; }; // The forward lookup of hosts on this domain zone " .co.uk" in { t

domain name system - bind and dns master and slave

After going through OReilly dns and bind book, I still have problems with a master and slave configuration, I am getting client 192.168.1.67#34245: update ' .co.uk/IN' denied as a syslog error for the master definintion of the zone. and named[19034]: client 192.168.1.67#47452: update forwarding ' .co.uk/IN' denied as a syslog error for the slave definition The server that has the master zones has a named.conf : options { allow-transfer { 192.168.1/24; }; } // The reverse lookup of 192.168.1.* - the local IP addresses zone "1.168.192.in-addr.arpa" in { type master; file "192.168.1.db"; allow-transfer { key TRANSFER; }; allow-update { key TRANSER; }; }; // The forward lookup of hosts on this domain zone " .co.uk" in { type master; file " .co.uk.db"; allow-transfer { key TRANSFER; }; allow-update { key TRANSER; }; }; key "TRANSFER" { algorithm hmac-md5; secret " "; }; #

domain name system - Questions about DNS, BIND and setup

itemprop="text"> I have a few questions which I can't find the answer. Is it possible to create two nameservers (ns1,ns2) with one IP ? To move my server DNS from godaddy to ns1/ns2.my_domain.com, I can use Bind ? If I install Bind, create a master zone (www, ns1, ns2, mail, pop, etc.), set it up. Then create second master zone (reverse), set it up. Log into godaddy account and change the nameservers to ns1/ns2.my_domain.com. Is it enough for the redirection to work ? Here's my named.conf : options { listen-on port 53 { 127.0.0.1; }; listen-on-v6 port 53 { ::1; }; directory "/var/named"; dump-file "/var/named/data/cache_dump.db"; statistics-file "/var/named/data/named_stats.txt"; memstatistics-file "/var/named/data/named_mem_s

domain name system - Questions about DNS, BIND and setup

I have a few questions which I can't find the answer. Is it possible to create two nameservers (ns1,ns2) with one IP ? To move my server DNS from godaddy to ns1/ns2.my_domain.com, I can use Bind ? If I install Bind, create a master zone (www, ns1, ns2, mail, pop, etc.), set it up. Then create second master zone (reverse), set it up. Log into godaddy account and change the nameservers to ns1/ns2.my_domain.com. Is it enough for the redirection to work ? Here's my named.conf : options { listen-on port 53 { 127.0.0.1; }; listen-on-v6 port 53 { ::1; }; directory "/var/named"; dump-file "/var/named/data/cache_dump.db"; statistics-file "/var/named/data/named_stats.txt"; memstatistics-file "/var/named/data/named_mem_stats.txt"; allow-query { localhost; }; recursion yes; dnssec-enable yes; dnssec-validation yes; dnssec-lookaside auto; /* Path to ISC DLV key */ bindkeys-file "

hosting - How to host two web sites on one IP? IIS

itemprop="text"> I'm a developer, and since I'm not that skilled with server stuff, I wanted to ask, is it possible to have multiple web sites on one IP? Say: foo.com -> 111.222.333.444 bar.com -> 111.222.333.444 The sites are different foo.com != bar.com Platform is Windows server/IIS6 itemprop="text"> class="normal">Answer Yes it is. You need to configure host header names for each web site. href="http://support.microsoft.com/kb/324287" rel="nofollow noreferrer">http://support.microsoft.com/kb/324287

hosting - How to host two web sites on one IP? IIS

I'm a developer, and since I'm not that skilled with server stuff, I wanted to ask, is it possible to have multiple web sites on one IP? Say: foo.com -> 111.222.333.444 bar.com -> 111.222.333.444 The sites are different foo.com != bar.com Platform is Windows server/IIS6 Answer Yes it is. You need to configure host header names for each web site. http://support.microsoft.com/kb/324287

fusionio - Stock Fusion-io ioDrive 2 on HP Proliant DL380p Gen8

We bought 2 Fusion-io ioDrive 2 PCIe Cards on a very good deal. They are 1.2 TB each. These cards are the stock Fusion-io Cards, not the HP rebranded ones (the ones with custom HP firmware) We have tried both cards on 2 different HPe DL380p gen8 servers, but none of them recognises any of the cards. Bios and iLO4 both say that PCIe slots are empty. We have tried different PCIe Slots and even different PCIe Risers. Since the servers don't detect them I can't even check which FW version they are running. Both DL380p servers have current firmware and ROM with SPP 10.16. I don't think the ioDrives are DOA, but I suspect there might be some compatibility issue. Before I return them, I would like to know if someone has tried these cards, but the stock Fusion-io (or Sandisk) on an HPe Gen8 server Any help or tip will be greatly appreciated

fusionio - Stock Fusion-io ioDrive 2 on HP Proliant DL380p Gen8

We bought 2 Fusion-io ioDrive 2 PCIe Cards on a very good deal. They are 1.2 TB each. These cards are the stock Fusion-io Cards, not the HP rebranded ones (the ones with custom HP firmware) We have tried both cards on 2 different HPe DL380p gen8 servers, but none of them recognises any of the cards. Bios and iLO4 both say that PCIe slots are empty. We have tried different PCIe Slots and even different PCIe Risers. Since the servers don't detect them I can't even check which FW version they are running. Both DL380p servers have current firmware and ROM with SPP 10.16. I don't think the ioDrives are DOA, but I suspect there might be some compatibility issue. Before I return them, I would like to know if someone has tried these cards, but the stock Fusion-io (or Sandisk) on an HPe Gen8 server Any help or tip will be greatly appreciated.

Windows Server Can't Connect through Network but Client Can Connect to Server

itemprop="text"> Edited now that I understand more the issue: My Windows 2008R2 server is having a strange networking problem. I can access the server via RDP, File Sharing, etc. But from the server, I can't connect to anything on the network - I can't connect to the email server, web servers, nothing! I could not find anything in the event log that is related. As I have 200+ users using the file share from it, I don't want to restart it until way late at night when nobody is using it. So I'm wondering if anybody knows what I should look for, anything I can do, etc, to remedy this without restarting. Also, what could be the cause - I obviously don't know that restarting it will resolve anything. Earlier post for info A Windows 2008R2 server is having issues accessing domain re

Windows Server Can't Connect through Network but Client Can Connect to Server

Edited now that I understand more the issue: My Windows 2008R2 server is having a strange networking problem. I can access the server via RDP, File Sharing, etc. But from the server, I can't connect to anything on the network - I can't connect to the email server, web servers, nothing! I could not find anything in the event log that is related. As I have 200+ users using the file share from it, I don't want to restart it until way late at night when nobody is using it. So I'm wondering if anybody knows what I should look for, anything I can do, etc, to remedy this without restarting. Also, what could be the cause - I obviously don't know that restarting it will resolve anything. Earlier post for info A Windows 2008R2 server is having issues accessing domain resources. For example when logged on to this server, if I try: \server1\ I get Error code 0x80004005 - Unspecified Error gpupdate fails with "The processing of Group Policy failed. Windows could not resolv

linux - Has this server been compromised?

itemprop="text"> A friend is running a VPS (CentOS) His business partner was the sysadmin but has left him high and dry to look after the system. So, I've been asked to help out in fixing an apparent spam problem. His IP address got blacklisted for unsolicited mail. I'm not sure where to look for a problem, but I started with netstat to see what open connections were running. It looks to me like he has remote hosts connected to his SMTP server. Here's the output: Active Internet connections (w/o servers) Proto Recv-Q Send-Q Local Address Foreign Address State tcp 0 0 78.153.208.195:imap 86-40-60-183-dynamic.:10029 ESTABLISHED tcp 0 0 78.153.208.195:imap 86-40-60-183-dynamic.:10010 ESTABLISHED tcp 0 1 78.153.208.195:35563 news.avanport.pt:smtp SYN_SENT tcp 0 0 78.153.208.195:35559 vip-us-br-mx.terra.com:smtp

linux - Has this server been compromised?

A friend is running a VPS (CentOS) His business partner was the sysadmin but has left him high and dry to look after the system. So, I've been asked to help out in fixing an apparent spam problem. His IP address got blacklisted for unsolicited mail. I'm not sure where to look for a problem, but I started with netstat to see what open connections were running. It looks to me like he has remote hosts connected to his SMTP server. Here's the output: Active Internet connections (w/o servers) Proto Recv-Q Send-Q Local Address Foreign Address State tcp 0 0 78.153.208.195:imap 86-40-60-183-dynamic.:10029 ESTABLISHED tcp 0 0 78.153.208.195:imap 86-40-60-183-dynamic.:10010 ESTABLISHED tcp 0 1 78.153.208.195:35563 news.avanport.pt:smtp SYN_SENT tcp 0 0 78.153.208.195:35559 vip-us-br-mx.terra.com:smtp TIME_WAIT tcp 0 0 78.153.208.195:35560

active directory - Build new domain server 2012 in parallel with existing windows domain server 2003

I have existing network with around 400 PCs on it working under windows xp professional and windows 7 professional too. Around 375 PCs are linked using static IP address and they are not connected to any domain server and only around 25 PCs are Linked to an existing domain server exist on the network working under windows server 2003 be cause of project that is stopped 5 years ago and no one control what happen on it and know nothing about it so as you can see their not much think to lose. Now I want to make new domain server but using Windows Server 2012 R2 I have installed Windows Server 2012 R2 and I am planning to activate the active direcory , DHCP , and DNS while these small number of PCs which are linked to the OLD windows domain server 2003 are ruining and I want to touch them for now since they

active directory - Build new domain server 2012 in parallel with existing windows domain server 2003

I have existing network with around 400 PCs on it working under windows xp professional and windows 7 professional too. Around 375 PCs are linked using static IP address and they are not connected to any domain server and only around 25 PCs are Linked to an existing domain server exist on the network working under windows server 2003 be cause of project that is stopped 5 years ago and no one control what happen on it and know nothing about it so as you can see their not much think to lose. Now I want to make new domain server but using Windows Server 2012 R2 I have installed Windows Server 2012 R2 and I am planning to activate the active direcory , DHCP , and DNS while these small number of PCs which are linked to the OLD windows domain server 2003 are ruining and I want to touch them for now since they are belong to high level employees. I want to slowly move all other PCs which are not connected to any domain server yet to join one by one with slow steps to the new domain ser

windows - What should I name my Active Directory?

There are a lot of really screwed up configurations out there, because people didn't take a minute to sit down and think about something as simple as the name for their Active Directory forest. I'm asking this question to self-answer so that this knowledge can be more readily available. If you think you have a better answer, by all means add your input (but be prepared to defend it!) So, what should I name my new Active Directory?

windows - What should I name my Active Directory?

There are a lot of really screwed up configurations out there, because people didn't take a minute to sit down and think about something as simple as the name for their Active Directory forest. I'm asking this question to self-answer so that this knowledge can be more readily available. If you think you have a better answer, by all means add your input (but be prepared to defend it!) So, what should I name my new Active Directory?

How do black holes mitigate ddos attacks?

I'm looking at how to try and prevent DDOS attacks before I launch a website as I will expect lots of online 'booters' to attack the server. I've read through lots of threads on here and stackoverflow and realised that at my own server its not worth setting anything up as the damage is already being done. This means I can either have a reverse proxy or try and work with my hosting provider. What i'm trying to understand is how null routing traffic is effective. Lets say that I have been able to identify the pattern of an attack and know which packets are from the attack, If I tell my hosting provider this and they decide to black hole these packets, isn't this still impacting their infrastructure? Because the bandwidth is still be used in order for the attacker to send the packet in the first place, they can

How do black holes mitigate ddos attacks?

I'm looking at how to try and prevent DDOS attacks before I launch a website as I will expect lots of online 'booters' to attack the server. I've read through lots of threads on here and stackoverflow and realised that at my own server its not worth setting anything up as the damage is already being done. This means I can either have a reverse proxy or try and work with my hosting provider. What i'm trying to understand is how null routing traffic is effective. Lets say that I have been able to identify the pattern of an attack and know which packets are from the attack, If I tell my hosting provider this and they decide to black hole these packets, isn't this still impacting their infrastructure? Because the bandwidth is still be used in order for the attacker to send the packet in the first place, they can keep sending them regardless of receiving no response so all the hosting provider is doing is keeping my service up but still taking the damage? Is this mea

routing behaviour (PAT/NAT)

itemprop="text"> |(eth0: 84.23.13.43) +--------------+ | | | NAT router | | | +--------------+ |(eth1: 192.168.0.1) | ---------------- ( ) +--+ ( ) |__|------( 192.168.0.0/24 ) /____\ ( ) Host-A (________________) (192.168.0.2) /> Assuming we have above network situation and a destination PAT/NAT rule configured on the NAT router for eth0 which forwards all incoming packages with destination port TCP/80 to Host-A (192.168.0.2) I have following question: What happens when a Host-B (192.168.0.10) in the local networks sends a HTTP request to 84.23.13.43? Some routers seem to manage this situation correctly others not. Is there a technical expression describing this situation? How can I find out which router can manage such internal request on an external ip and which not? class=&q

routing behaviour (PAT/NAT)

|(eth0: 84.23.13.43) +--------------+ | | | NAT router | | | +--------------+ |(eth1: 192.168.0.1) | ---------------- ( ) +--+ ( ) |__|------( 192.168.0.0/24 ) /____\ ( ) Host-A (________________) (192.168.0.2) Assuming we have above network situation and a destination PAT/NAT rule configured on the NAT router for eth0 which forwards all incoming packages with destination port TCP/80 to Host-A (192.168.0.2) I have following question: What happens when a Host-B (192.168.0.10) in the local networks sends a HTTP request to 84.23.13.43? Some routers seem to manage this situation correctly others not. Is there a technical expression describing this si

ntp - all my ntpd servers marked falsetick, why?

I have a set of four ntpd servers that sync time from the same stratum 1 server. But on some clients they all are marked falsetick, why? remote refid st t when poll reach delay offset jitter ============================================================================== x10.201.24.36 209.51.161.238 2 u 12 64 377 0.177 464.794 1.136 x10.201.13.99 209.51.161.238 2 u 37 64 377 0.148 463.427 0.541 x10.201.24.37 209.51.161.238 2 u 817 1024 377 0.174 462.235 0.143 x10.201.12.198 209.51.161.238 2 u 853 1024 377 0.158 462.151 302.364 *127.127.1.0 .LOCL. 10 l 48 64 377 0.000 0.000 0.004 They recover from time to time, but why does it happen at all? Also another question is why do I have such a big offset? I tried to leave only 1 ntp server, but offset doesn't go down anyway. remote refid st t when poll reach delay offset jit

ntp - all my ntpd servers marked falsetick, why?

I have a set of four ntpd servers that sync time from the same stratum 1 server. But on some clients they all are marked falsetick, why? remote refid st t when poll reach delay offset jitter ============================================================================== x10.201.24.36 209.51.161.238 2 u 12 64 377 0.177 464.794 1.136 x10.201.13.99 209.51.161.238 2 u 37 64 377 0.148 463.427 0.541 x10.201.24.37 209.51.161.238 2 u 817 1024 377 0.174 462.235 0.143 x10.201.12.198 209.51.161.238 2 u 853 1024 377 0.158 462.151 302.364 *127.127.1.0 .LOCL. 10 l 48 64 377 0.000 0.000 0.004 They recover from time to time, but why does it happen at all? Also another question is why do I have such a big offset? I tried to leave only 1 ntp server, but offset doesn't go down anyway. remote refid st t when poll reach delay offset jitter ===================================