{"id":4308,"date":"2015-11-24T11:22:32","date_gmt":"2015-11-24T17:22:32","guid":{"rendered":"https:\/\/www.poweradmin.com\/blog\/?p=4308"},"modified":"2015-11-24T12:50:33","modified_gmt":"2015-11-24T18:50:33","slug":"simulating-a-large-network","status":"publish","type":"post","link":"https:\/\/www.poweradmin.com\/blog\/simulating-a-large-network\/","title":{"rendered":"Simulating a Large Network"},"content":{"rendered":"

We live, eat, breathe and love monitoring here at Power Admin. \u00a0So we\u2019re always looking for ways to improve. \u00a0One way is to scale our software to handle ever increasing loads. \u00a0<\/span><\/p>\n

\u00a0<\/p>\n

Some of our larger customers (the largest anti-virus and computer security software company in America which starts with \u2018Sym\u2019 and ends with \u2018antec\u2019, and a very well known operating system company frequently known as MS) have networks far, far larger than our own. \u00a0So we needed a way to at least simulate their needs in our software. \u00a0One way we did that was by setting up our LAB_BEAST server \ud83d\ude42<\/span><\/p>\n

\u00a0<\/p>\n

Multiple NICs<\/span><\/h3>\n

LAB_BEAST is a Windows 2012 R2 VM running on an ESX 5.5 host. \u00a0Despite the name, we didn\u2019t assign it huge resources, although it did get 3 NIC cards.<\/span><\/p>\n

\u00a0<\/p>\n

\"lab<\/a><\/span><\/p>\n

\u00a0<\/p>\n

In Windows we see that we have the three network connections showing up nicely.<\/span><\/p>\n

\u00a0<\/p>\n

\"lab<\/a><\/span><\/p>\n

\u00a0<\/p>\n

We assigned them 192.168.8.1, 192.168.9.1 and 192.168.10.1 respectively. \u00a0Since we want them to be on the network with the rest of the servers we had to change our typical netmask from\u00a0255.255.255.0 to 255.255.240.0 which will <\/span>give us a nice little range to add additional IP addresses.<\/span><\/p>\n

Multiple IP Addresses<\/span><\/h3>\n

Now for the secret sauce \u2013 each network conne<\/span>ction can have more than one IP address assigned to it! \u00a0The steps below show how that is done.<\/span><\/p>\n

\u00a0<\/p>\n

\"add\u00a0 \u00a0\"add\u00a0 \u00a0\"add<\/a><\/span><\/p>\n

\u00a0<\/p>\n

So the secret is to add many IP addresses to each network connection. \u00a0We found by doing a little research that Windows will apparently allow up to 255 addresses per connection. \u00a0Just to make it simple, we assigned xxx.xxx.xxx.1 to xxx.xxx.xxx.250 to each. \u00a0That means our lab server now has 750 IP addresses!<\/span><\/p>\n

\u00a0<\/p>\n

When we started we setup the first 100 IP addresses manually as shown above. \u00a0That\u2019s very tedious. \u00a0But then we found this great\u00a0post over at How-To Geek:\u00a0How to Quickly Add Multiple IP Addresses to Windows Servers<\/a><\/span><\/p>\n

\u00a0<\/p>\n

So in our case we just needed to run these three commands:<\/span><\/p>\n

\u00a0<\/p>\n

FOR \/L %A IN (0,1,250) DO netsh interface ipv4 add address \u201cEthernet\u201d\u00a0 \u00a0192.168.8.%A 255.255.240.0<\/span><\/p>\n

FOR \/L %A IN (0,1,250) DO netsh interface ipv4 add address \u201cEthernet 2\u201d 192.168.9.%A 255.255.240.0<\/span><\/p>\n

FOR \/L %A IN (0,1,250) DO netsh interface ipv4 add address \u201cEthernet 3\u201d 192.168.10.%A 255.255.240.0<\/span><\/p>\n

\u00a0<\/p>\n

So now LAB_BEAST handles requests to these three IP address ranges:<\/span><\/p>\n

\u00a0<\/p>\n

192.168.8.1 \u2013 192.168.8.250,\u00a0<\/span><\/p>\n

192.168.9.1 \u2013 192.168.9.250<\/span><\/p>\n

192.168.10.1 \u2013 192.168.10.250<\/span><\/p>\n

\u00a0<\/p>\n

Essentially, this one server acts and responds as though it is 750 different\u00a0Windows servers on the network.<\/span><\/p>\n

\u00a0<\/p>\n

Monitoring Load<\/span><\/h3>\n

You might ask how bogged down it gets. \u00a0So far we\u2019ve setup monitors to check for: Ping<\/a>, free disk space<\/a> and a variety of performance counters<\/a> on all of those IP addresses. \u00a0As you can see in the PA Server Monitor charts<\/a> below, LAB_BEAST is\u00a0not even struggling:<\/span><\/p>\n

\"lab<\/a><\/p>\n

\u00a0<\/p>\n

What\u2019s even more surprising, is we have an external Satellite monitoring some of these IP addresses as well, so the server is actually getting hit as though it was 1000 separate devices. \u00a0Amazing.<\/span><\/p>\n

\u00a0<\/p>\n

Now, we chose those three particular monitors for a reason \u2014 they are very light weight. \u00a0Monitoring services and the Event Log is a little heavier. \u00a0Monitoring services and the Event Log for one server is no big deal \u2014 the server doesn\u2019t even feel it. \u00a0I suspect multiplying it by 1000 might have some impact \u2013 that\u2019s a test yet to come.<\/span><\/p>\n

\u00a0<\/p>\n

What\u2019s next?<\/span><\/h3>\n

Monitoring 1000 server\/devices is nice. \u00a0But our customers monitor MUCH\u00a0more than that. \u00a0And all from a single PA Server Monitor installation. \u00a0So\u00a0we\u2019ve setup a few other servers like LAB_BEAST to push the limits. \u00a0<\/span><\/p>\n

\u00a0<\/p>\n

We know from speaking with customers that a single PA Server Monitor installation can easily monitor 2000+ real servers\/devices<\/a> from a single installation. \u00a0We\u2019ll see how much further we can push it \ud83d\ude42<\/span><\/p>\n

\u00a0<\/p>\n","protected":false},"excerpt":{"rendered":"

We live, eat, breathe and love monitoring here at Power Admin. \u00a0So we\u2019re always looking for ways to improve. \u00a0One way is to scale our software to handle ever increasing loads. \u00a0 \u00a0 Some of our larger customers (the largest anti-virus and computer security software company in America which starts with \u2018Sym\u2019 and ends with […]<\/p>\n","protected":false},"author":3,"featured_media":4309,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4,5,10,9,8],"tags":[],"class_list":["post-4308","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-general-it","category-how-to","category-power-admin","category-technical","category-windows"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/www.poweradmin.com\/blog\/wp-json\/wp\/v2\/posts\/4308","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.poweradmin.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.poweradmin.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.poweradmin.com\/blog\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/www.poweradmin.com\/blog\/wp-json\/wp\/v2\/comments?post=4308"}],"version-history":[{"count":5,"href":"https:\/\/www.poweradmin.com\/blog\/wp-json\/wp\/v2\/posts\/4308\/revisions"}],"predecessor-version":[{"id":4322,"href":"https:\/\/www.poweradmin.com\/blog\/wp-json\/wp\/v2\/posts\/4308\/revisions\/4322"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.poweradmin.com\/blog\/wp-json\/wp\/v2\/media\/4309"}],"wp:attachment":[{"href":"https:\/\/www.poweradmin.com\/blog\/wp-json\/wp\/v2\/media?parent=4308"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.poweradmin.com\/blog\/wp-json\/wp\/v2\/categories?post=4308"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.poweradmin.com\/blog\/wp-json\/wp\/v2\/tags?post=4308"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}